Category: Notes

How to prevent search engines from indexing only the main page of the site

To prevent search engines from indexing only the main page, while allowing indexing of all other pages, you can use several approaches, depending on the characteristics of a particular site.

1. Using the robots.txt file

If the main page has its own address (usually it is index.php, index.html, index.htm, main.html and so on), and while trying to open a link like a website redirects to the main page, for example, to, then you can use the robots.txt file with something like the following content:

User-agent: *
Disallow: /index.php
Disallow: /index.html
Disallow: /index.htm
Disallow: /main.html

In fact, using an explicit name for the main page is the exception rather than the rule. So let's look at other options.

You can use the following approach:

  1. Deny site-wide access with the “Disallow” directive.
  2. Then allow the indexing of the entire site using the “Allow” directive, except for the main page.

Sample robots.txt file:

User-agent: *
Allow: ?p=
Disallow: /

The “Allow” directive must always come before “Disallow”. The “Allow” directive allows all pages with a URL like “?p=”, and the “Disallow” directive disables all pages. As a result, the following result is obtained: indexing of the entire site (including the main page) is prohibited, except for pages with an address like “?p=”.

Let's look at the result of checking two URLs:

  • (main page) – indexing is prohibited
  • (article page) – indexing allowed

In the screenshot, number 1 marks the contents of the robots.txt file, number 2 is the URL being checked, and number 3 is the result of the check.

2. Using the robots meta tag

If your site is separate files, then add the robots meta tag to the HTML code of the main page file:

<meta name="robots" content="noindex,nofollow>

3. With .htaccess and mod_rewrite

Using .htaccess and mod_rewrite, you can block access to a specific file as follows:

RewriteEngine On
RewriteCond %{HTTP_USER_AGENT} Google [NC,OR]
RewriteCond %{HTTP_USER_AGENT} Yandex [NC]
RewriteRule (index.php)|(index.htm)|(index.html) - [F]

Please note that when you try to open a link like (that is, without specifying the name of the main page), a specific file is still requested on the web server side, for example, index.php, index.htm or index. html. Therefore, this method of blocking access (and, accordingly, indexing) works even if the main page of your site opens without specifying a specific file name (index.php, index.html, index.htm, main.html, and so on), as is usually the case.

How to enable saving photos in HEIC (HEIF) format in Android and whether it should be done

As an alternative to JPEG, modern phone cameras offer saving images in the HEIC (HEIF) format.

Moreover, in iOS, the camera uses HEIC (HEIF) formats by default, and if you do not want to save your photos in these formats, then you can disable this feature.

Android phone cameras also support this format, but it is not used by default.

This guide will show you how to enable saving files in HEIF in Android. Information about this format will also be given so that you decide if you need it at all.

How to enable saving photos in HEIF format in Android camera

Open the Camera app.

Go to the camera settings by clicking the gear symbol.

Go to the “Picture formats” section.

Find and turn on the item “High efficiency pictures”.

The description of this item says: Save space by capturing Photo mode pictures in high efficiency image format (HEIF). Some apps and websites don’t support HEIF format.

After that, all new photos will be saved in HEIF format.

Actually photo files will be saved with .heic extension, not .heif. Applications that support this format understand both file extensions. HEIC is a container format that can store HEVC encoded sounds and images.

Do I need to enable saving photos in HEIF format in Android

HEIF is a new image encoding format, thanks to new algorithms, photo files take up many times less space, while the quality is better compared to JPEG. In addition, the HEIF format has additional technical advantages that are completely absent in JPEG.

At first glance, everything is wonderful.

But in practice, using the HEIF format, you will encounter the fact that many applications and sites do not understand it and do not know how to work with it, or work in a limited way. For example, web browsers cannot display HEIF images.

Even more frustrating is the fact that HEIF is already kind of an outdated format. Yes, despite the fact that HEIF is poorly supported by popular applications, the developers of this format have created another format that is even better, this is AVIF.

Paradoxically, the even newer AVIF format is supported somewhat better by applications. Web browsers are at least partially capable of displaying images in this format. Partly because animated AVIF (yes, the format supports animated images, transparency, and deeper color depth) is not supported by any of the applications I've tested, including web browsers.

But what is even more annoying, even modern Android phone models still do not have the option to save photos in AVIF.

If your phone does not yet support HEIC (HEIF) formats, then I took some photos for you so that you can compare the quality with JPEG and HEIC (HEIF).

This photo was taken with my phone and saved as a JPEG.

Then I enabled saving the file in the HEIC format in the settings and took the following picture (the web browser cannot display this format, but you can download the file from the link):

JPEG file size 2.5 MB, HEIF file size taken on the phone 1.4 MB.

I'm not completely sure if the phone actually saves the file in HEIC format initially, or if it first takes a picture in JPEG format and only then converts it to HEIC. In the second case, all the advantages (less distortion during compression, support for greater color depth) of the HEIC format are lost, except for the small size.

Then I took the JPEG file and converted it to HEIC. In fact, in this case, HEIC and HEIF are identical formats. The file turned out to be upside down, to rotate it 90° I used the GIMP graphics editor. In both cases, I converted and saved the file without changing the resolution or reducing the quality. The resulting file began to occupy 663 kilobytes at the same resolution. Link to the file:

Visually, the files do not differ – you can download all three files and look for differences in order to decide for yourself whether it is worth switching to the HEIC (HEIF) format, given the difficulties with viewing and processing it.

You can also experiment with AVIF and HEIF (HEIC) formats using the Universal Image Converter: This completely free online service supports hundreds of image formats, including AVIF and HEIF (HEIC).

Why images are distorted in photographs and parallel lines become converging

I noticed that the photos taken by the Android phone, namely the Samsung Galaxy S21 Ultra models, are very distorted.

Distortion is especially noticeable on parallel lines (such as the sides of a building) and on people's faces.

For example, In the photo above you can see that tall buildings seem to grow in different directions, although this is certainly not the case – in real life, such high-rise buildings would have already fallen.

Even in this photo of a low building with several floors, you can see how much the photo is distorted – the parallel sides are not parallel at all.

The same happens with faces – they become distorted, as if alien.

This camera behavior and photo distortion cannot be avoided when shooting with a wide-angle lens, but the examples shown above are taken with a regular camera without any adjustments.

In fact, the problem is explained and solved very simply – you need to hold the phone perpendicular to the object that you are photographing.

Look at this distorted frame – the lines of its sides are no longer parallel and should converge at some point.

And in this shot, the photographer is simply holding the phone perpendicular to the frame – now all opposite sides of the picture are parallel!

If you are photographing houses, then in order for their sides to be parallel, mentally divide the viewfinder horizontally in half and place the center of the house on this line. That is, the house does not have to be placed exactly in the center of the frame, it is enough that the middle of the house is at the level of a mental line dividing the frame horizontally in half.

In this photo, I slightly changed the angle of the house opposite and its walls began to go straight up.

Likewise with faces. Try to make sure that the camera is held perpendicular to the face, that is, the middle part of the face should be at the level of the mental line dividing the frame horizontally in half.

How to measure distance (route and direct) between two points on Google maps

Table of contents

1. What is the difference between the distances directly and the route between two objects on the map

2. How to measure a route between two points on the map

2.1 How to measure a route between two points on the map on a computer

2.2 How to change the route between two objects on the map in Android

3. How to measure the direct distance between two objects on a map

3.1 How to measure the direct distance between two objects on a map on a computer

3.2 How to measure the direct distance between two objects on a map on Android

3.3 How to measure the direct distance between two objects on a map on iOS (iPhone & iPad)

What is the difference between the distances directly and the route between two objects on the map

The distance between two points can be measured as:

  • distances directly from one geographic feature to another
  • the distance of the route that you need to walk or drive to get from one point to another

Although these distances are related to each other, they are rarely the same. For example, in a city with tangled roads, the distance between two objects (for example, a house and a sea beach) may be 1.4 km in a straight line, but in practice, in order to get to the beach from the house on foot, you need to walk 2.1 km – because somewhere the roads form a fancy cobweb, some parts of the route are closed.. That is, these two distances differ by 50%. If we also take into account transport (cars, for example) and public transport, then the difference between these two distances will be even more significant.

In this post we will look at how to determine the distance between two objects on maps in a straight line and the distance of the route between them. We will learn how to do this on a desktop computer, as well as Android and iOS devices.

How to measure a route between two points on the map

How to measure a route between two points on the map on a computer

Go to Google Maps:

Then click on the “Directions” button:

You will see two fields. Click on the first one. You can enter an address to search. Another option is to specify the location directly on the map, for this click the magnifying glass (“Search”) and select the desired location on the map.

Now switch to the second field and select your destination in the same way.

Then select the method of travel (Recommended travel mode, Driving, Transit, Waling, Cycling, Flights).

You will see options for the shortest (or fastest, most convenient) routes, distance and travel time.

You can drag both the end and the starting point of the route, and each time the route will be rebuilt based on new initial data and you will receive updated information about the distance and time of movement.

If you want to change the path of the route, then you can drag any waypoints and select the desired route. For the new route, you will receive the calculated distance and travel time.

If you want to create a complex route, then click the “Add destination” button.

Note: if you have already performed a search on Google Maps, then to switch to the route building mode, click the “Directions” button.

The already familiar window will open, you just need to specify the second (starting) point of the route.

Optionally, you can swap the starting and ending points.

How to change the route between two objects on the map in Android

Open the Google Maps app.

Select the first object on the map by clicking on it, or use the search to select it.

Then click the “Directions” button.

Select the second point. If you want to swap the starting and ending points, then click on the symbol of the two arrows pointing up and down.

Second point selection options:

  • search
  • your current location
  • point on the map

For example, I select the second point on the map, when everything is ready, click OK.

Then choose a method of transportation (Recommended travel mode, Driving, Transit, Waling, Cycling, Flights).

You will be shown the length of the route and the time it will take to get there by the chosen method of travel.

As with the desktop version, you can switch between the suggested routes and estimate the length of each one.

How to measure the direct distance between two objects on a map

You can calculate the distance between two or more points on the map. For example, you can measure the mileage in a straight line between two cities.

How to measure the direct distance between two objects on a map on a computer

On your computer, open Google Maps. If you're using Maps in Lite mode, you’ll see a lightning bolt at the bottom and you won't be able to measure the distance between points.

Right-click on your starting point.

Choose “Measure distance”.

Click anywhere on the map to create a path to measure. To add another point, click anywhere on the map.

Optional: Drag a point or path to move it, or click a point to remove it.

At the bottom, you’ll see the total distance in miles (mi) and kilometers (km).

When done: On the card at the bottom, click Close Close.

How to measure the direct distance between two objects on a map on Android

Step 1: Add the first point

  1. On your Android phone or tablet, open the Google Maps app Google Maps.
  2. Touch and hold anywhere on the map. You'll see a red pin appear.
  3. At the bottom, tap the name of the place.

  1. On the place’s page, scroll down and choose Measure distance.

Step 2: Add the next point or points

  1. Move the map so that the black circle, or crosshairs, is on the next point you want to add.

  1. At the bottom right, tap Add.
  2. Add points until you're done.

Step 3: Get the distance

  1. At the bottom, you’ll see the total distance in miles (mi) or kilometers (km).
  • Optional: To remove the last point you added, tap Undo. To clear all points: At the top right, tap More and then Clear.
  1. When done, tap the back arrow in the top left.

Important note: Apparently, “Measure distance” does not appear if you select an organization. This inscription appears if you select a road or other empty place for which there is no detailed description.

How to measure the direct distance between two objects on a map on iOS (iPhone & iPad)

Step 1: Add the first point

  1. On your iPhone or iPad, open the Google Maps app Google Maps.
  2. Touch and hold anywhere on the map. You'll see a red pin appear.
  3. At the bottom, tap the name of the place.
  4. On the place’s page, scroll down and choose Measure distance.

Step 2: Add the next point or points

  1. Move the map so that the black circle, or crosshairs, is on the next point you want to add.
  2. At the bottom right, tap Add.
  3. Add points until you're done.

Step 3: Get the distance

  1. At the bottom, you’ll see the total distance in miles (mi) or kilometers (km).
  • Optional: To remove the last point you added, tap Undo. To clear all points: At the top right, tap More and then Clear.
  1. When done, tap the back arrow in the top left.

Gmail does not receive forwarded emails (SOLVED)

Some Gmail users face the problem that the configured forwarding to the Google mailbox (Gmail) does not work, or is unstable.

I faced such a problem when trying to set up forwarding from mail to mail. In my case, forwarding from was configured correctly and enabled. Moreover, it even worked for some time.

Google has shown that the problem when forwarded emails are not being delivered is encountered by many users – there is no official solution to the problem from Google.

First of all, it is recommended to check the filters in Gmail – some of them can send mail to spam or delete emails without putting them in the Inbox. Instead of going into the filters and trying to figure them out, just send a letter from the mailbox from which you set up forwarding to the address where you want to forward – if the electronic letter has arrived, then it is not about filters.

Instead of trying to fix unstable forwarded emails, there is another, more reliable way out. You can set up Gmail to check and receive mail from other mailboxes.

How to set up Gmail to check mail from other mailboxes

Go to Gmail mailbox, click the gear in the upper right corner and select “See all settings”.

Go to the “Accounts and Import” tab. Find the “Check mail from other accounts” section and click “Add a mail account”.

Enter the email address from which you want to forward emails as soon as they arrive.

Select “Import emails from my other account (POP3)”.

Enter your mailbox password.

Next, you will be asked if you want to be able to send electronic letters from this account. If so, you just need to enter the password again.

This method turned out to be more reliable than forwarding emails. You need to remember that emails will stop being forwarded (coming to your Gmail mailbox) if you change the password for the forwarded mailbox, so when you change your password, do not forget to change it in the Gmail settings.

How to block access to my site from a specific bux site or any other site with negative traffic

There are situations when negative traffic comes from certain sites, for example, from bux sites or simply from sites that you don't like. In some cases, such traffic can be dealt with, but not always.

Quite often, there are tasks like “go to a search engine, enter such and such a query, go to such and such a site” in bux sites – this is unlikely to be combated, since this request is difficult to distinguish from ordinary traffic.

But if the request is made directly from the bux site, or is shown in an iframe, then this can be dealt with.

Also, if your site has been added to an aggregator or a link is placed on a site that you do not like, then this method will also work.

For example, a bad site is To block traffic from this site, you can use the following:

RewriteCond %{HTTP_REFERER} [NC]
RewriteRule .* - [R=404]

These lines need to be written to the .htaccess file. These are the rules for the mod_rewrite module, which is usually enabled in Apache.

In this case, everyone who came from the site will be shown the message “404 page not found”. If desired, you can put any other response code instead of 404, for example, 403 (access denied), 500 (internal server error) or any other.

If you want to block access from multiple sites, use the [OR] flag, for example:

RewriteCond %{HTTP_REFERER} [NC,OR]
RewriteCond %{HTTP_REFERER} anotherdomain\.com [NC,OR]
RewriteCond %{HTTP_REFERER} andanotherdomain\.com [NC,OR]
RewriteCond %{HTTP_REFERER} onemoredomain\.com [NC]
RewriteRule .* - [R=404]

Note that the [OR] flag does not need to be specified on the last line.

Instead of displaying an error, you can redirect to any page of your site, for example, in the following case, all users who come from the site will be sent to the error.html page of your site:

RewriteCond %{HTTP_REFERER} [NC]
RewriteRule .* error.html [R]

And the following rules set everyone who came from the site to redirect to

RewriteCond %{HTTP_REFERER} [NC]
RewriteRule .* [R]

How to change the language of Google services

Google services are available in all languages supported by Google. You can change your account language at any time.

What does the change of language affect?

If you change your preferred language, you will be shown different content on the Internet. Google may use information about your chosen languages to display more relevant content on apps and services. To change your preferred language for mobile apps, go to the language settings on your device.

That is, first of all, changes in the language in Google services affect:

  1. The interface language, for example, in GMail.
  2. Suggested search results, they will be targeted to the selected language
  3. Advertising. The language you choose is one of the factors in which ads are shown to you.

How to change Google search language

To ensure that you are less likely to see sites in your current language and prioritize sites in your chosen language, change the language of Google services.

However, this does not mean that you will no longer be shown results in search results in languages other than the selected one. The fact is that search results are generated based on many factors, for example, the language of your web browser and the language of previously viewed websites.

If you do not want to change the language of all Google services, but want to change only the preferred language of the search results, then go to the website, search and click on the gear located to the right of the search bar.

In the menu that appears, select the “Language” item.

Select the desired search language and save your changes.

How to change the interface language of Google services

1. Sign in to your Google account.

2. Go to

3. Click the “Add another language” button or if the language you need is present in the “Added by Google” section, that is, added automatically, then click the “Save” button.

4. Select the language and dialect of the language and click the “Save” button.

5. Press the up arrow to prioritize the selected language.

You may need to restart your web browser for the changes to take effect.

If you want to return your language settings or select a different language, go back to and select your preferred language by clicking the up arrow next to it.

How to copy a Google map created by another user

Google Maps allows you to create your own maps by adding places, routes, markers, layers, information, areas. Sometimes users create very useful maps. Since this is a user's map, he, by his own decision, can change it, delete it or remove it from public access – sometimes it is a pity to lose access to the map, which is a storehouse of data and is the result of long and painstaking work. This article will show you how you can make a copy of a Google Map and have it even if the original map is no longer available or has changes that you don't like.

There is no copying option in the settings and actions with Google maps, but this does not mean that it is impossible.

Open the map you are interested in in a web browser, then go to and select the “Recent” tab.

Find the map you are interested in and click the button of three points, in the menu that opens, select “Copy”.

Now go to the “Owned” tab.

There you will find the copied map.

How to edit someone else's Google map

If you do not have permission to edit someone else's Google map, but you want to make changes to the map, then you need to copy the map, as shown above, you can edit this copied map.

Where Google maps are copied

Maps are copied to Google Drive. You will find your copy of the map at

How to make a map available to other users

By default, the copied map is available only to you. If you want to allow other people to access it, then open your copy of the map, and click the “Share” message.

Enable Preferred Access - Link Only or Full Access.

Copy the link to the map you want to share.

How to add a map to a site

To add a map to the site, open it, click the three-dot button, in the menu that opens, select “Embed on my site”.

You will be given a snippet of HTML code to insert a map into a website page.

How to wash your sneakers properly

Can my sneakers be machine washed?

About the fact that sneakers can be washed, I myself learned relatively recently. I like light-colored shoes or shoes with light-colored inserts, so they need to be looked after regularly.

I usually just wash my sneakers with a soapy sponge. But once communicating with a rather young acquaintance, I heard from her something about washing sneakers.

I asked:

- Can sneakers be washed in a washing machine?

She answered:

- Can… if mom doesn't see)))

In general, I washed my rather worn Zara trainers this way a couple of times and they looked good. But the third time after washing, holes appeared on them and the sneakers had to be thrown out.

That is, in principle, it is possible to wash sneakers, but, firstly, not everything, and, secondly, it must be done correctly.

Which sneakers can be washed in a washing machine

I got into a conversation about washing sneakers with a shoe saleswoman and she explained everything to me.

So, leather sneakers (like the one in the title photo above) cannot be washed. That is, you can wash them when you no longer feel sorry for them. In general, wash new leather sneakers the old fashioned way with a sponge and soap.

You can wash rag sneakers. An example of sneakers that can be washed in the photo below. After washing, they look like new:

How to properly wash sneakers in a washing machine

The most important thing is to choose the most gentle mode, namely:

  • minimum time
  • non-hot water
  • minimum spin speed or no spin at all

An example of my settings:

  • the program “Fast 30 minutes” is selected
  • I turned off the spin, so the washing time was reduced to 21 minutes
  • water temperature 20 ℃

Turning off the spin is a controversial decision, since the sneakers will have to be dried for at least a day and a lot of water will flow out of them. But I feel sorry for my sneakers, so I go to such inconvenience. Alternatively, you can choose to dry at 400 rpm.

Select the temperature in the range of 20-30 ℃. I don't have 30 ℃ in my washing machine settings, so I chose 20 ℃.

Insoles and so on usually do not need to be pulled out – in my opinion, in all modern sneakers they are simply glued.

I add one capsule of detergent.

As a result, the sneakers are clean and pleasantly scented.

The question of whether it is possible to wash sneakers along with clothes remains open))) But I would not recommend))

Intel disabled undervolting on 11th gen Tiger Lake CPUs

Owners of new computers, as well as users updating the BIOS of their laptops and computers, may have noticed that manufacturers have a tendency to disable undervolting. 10th Gen processors ship with undervolting disabled by default. To enable it, you need to find the appropriate setting in the depths of the BIOS.

If you have previous generations of central processors and after updating the BIOS, you notice that the undervolting has stopped working, then the matter is in this update.

And not everyone is lucky: sometimes manufacturers block the possibility of undervolting and do not offer any options to re-enable it. The only option in such a situation is to rollback BIOS to the previous version.

And now, in Intel 11th generation processors, undervolting is completely disabled, at the hardware level. There is no other way to turn it on.

The official reason? Vulnerability allowing Plundervolt attack.

How dangerous is a Plundervolt attack? All of the following conditions must be met:

1. Physical access (!) to a computer with an Intel processor

2. Elevated privileges (root rights) (!)

3. 3. Sophisticated software that drastically (-200-300mV range) lowering the voltage in a bizarre way causes malfunctions in calculations and access to the SGX…

4. This vulnerability is only possible on Intel Software Guard Extensions (SGX). Do you know what this is? I do not know either. This is something complex and very rarely (never?) used by regular users.

You may ask, why does this attack even need undervolting if you already have physical access and already have root rights? After all, even using one of these, you can get full access over the computer and do anything with it. The only reason people talk about this vulnerability is the possibility of an attack on SGX. But the site itself says:

If you do not use SGX, you do not need to do anything.

That is the attack does not apply to your computer.

The question is, how reliable are attacks with a strong decrease in voltage in general, if the computer in such cases prefers to simply freeze or go into a reboot?

Why for an attack that is impossible in real conditions and is not exploited by anyone due to the fact that it is pointless/impossible to exploit, it was necessary to completely block the possibility of undervolting? Why not give the “risky guys” an opportunity to turn on undervolting if they are willing to accept non-existent risk?

All these unanswered questions suggest that Intel wants users to buy more expensive processors if they lack the power or TDP.

First of all, owners of laptops, especially ultrabook models, will lose from the prohibition of undervolting. It is difficult to provide good cooling in them and undervolting was the Holy Grail for them. Especially unpleasant for the owner of powerful (gaming) laptops.

Undervolting allows you to use central processors more efficiently, thanks to it they overheat less, consume less energy, keep high frequencies longer (throttling happens less often), and more productive generally. It is a pity that 11th generation Intel processors are deprived of all this due to some phantom danger.

Moreover, it is written on the Plundervolt site, Intel has already released a patch that eliminates this vulnerability.