What is a cookie?

A cookie is a harmless text file that is stored in your browser when you visit almost any web page. The usefulness of the cookie is that the website is able to remember your visit when you return to browse that page. Although many people do not know, cookies have been used for 20 years, when the first browsers appeared for the World Wide Web.
What is NOT a cookie?

It is not a virus, a Trojan, a worm, spam, spyware or pop-up windows.
What information does a cookie store?

Cookies do not usually store sensitive information about you, such as credit cards or bank details, photographs, your ID or personal information, etc. The data they store are of a technical nature, personal preferences, personalisation of contents, etc.

The web server does not associate you as a person but with your web browser. In fact, if you browse regularly with Internet Explorer and try browsing the same website with Firefox or Chrome you will see that the website does not realize that you are the same person because you are actually associating the browser, not the person.
What kind of cookies are there?

Technical Cookies: These are the most basic and allow, among other things, to know when a human is surfing or an automated application, when an anonymous user and a registered one are surfing, basic tasks for the functioning of any dynamic web.
Analysis Cookies: They collect information about the type of navigation you are carrying out, the sections you use the most, the products you consult, the time of use, the language, etc.
Advertising Cookies: Display advertising based on your browsing, country of origin, language, etc..

What are your own cookies and those of third parties?

Your own cookies are those generated by the page you are visiting and those of third parties are those generated by external services or providers such as Facebook, Twitter, Google, etc..
What happens if I turn off cookies?

To help you understand the extent to which you can disable cookies, here are a few examples:

You will not be able to share content from this website on Facebook, Twitter or any other social network.
The website will not be able to adapt the content to your personal preferences, as is often the case in online shops.
You will not be able to access the personal area of that website, such as My Account, or My Profile or My Orders.
Online stores: You will be unable to make purchases online, they will have to be telephone or visiting the physical store if you have it.
It will not be possible to customise your geographical preferences such as time zone, currency or language.
The website will not be able to perform web analytics on visitors and traffic to the website, which will make it difficult for the website to be competitive.
You will not be able to write on the blog, you will not be able to upload photos, publish comments, rate or rate content. The web will not be able to know if you are a human or an automated application that publishes spam.
It will not be possible to show sectorized advertising, which will reduce the advertising income of the web.
All social networks use cookies, if you deactivate them you will not be able to use any social network.

Can cookies be deleted?

Yes, not only delete, but also block, in a general or particular way for a specific domain.

To delete cookies from a website you must go to the settings of your browser and there you can search for those associated with the domain in question and proceed to delete them.
Cookie settings for the most popular browsers

Here’s how to access a specific cookie from your Chrome browser. Note: These steps may vary depending on the browser version:

Go to Settings or Preferences via the File menu or by clicking on the customisation icon at the top right.
You will see different sections, click on the option Show advanced options.
Go to Privacy, Content Settings.
Select All Cookies and Site Data.
A list of all cookies sorted by domain will appear. To make it easier for you to find the cookies for a particular domain, enter part or all of the address in the Search for cookies field.
After carrying out this filter, one or more lines with the cookies of the requested website will appear on the screen. Now all you have to do is select it and press the X to delete it.

To access the cookie settings of your Internet Explorer browser follow these steps (they may vary depending on the version of your browser):

Go to Tools, Internet Options
Click on Privacy.
Move the slider to adjust the privacy level you want.

To access your Firefox browser’s cookie settings follow these steps (they may vary depending on your browser’s version):

Go to Options or Preferences according to your operating system.
Click on Privacy.
Under History choose Use a custom setting for history.
You will now see the Accept cookies option, you can enable or disable it according to your preferences.

To access the Safari browser’s cookie settings for OSX follow these steps (they may vary depending on your browser version):

Go to Preferences, then Privacy.
Here you’ll see the Block Cookies option to adjust the type of block you want to perform.

To access your Safari browser’s cookie settings for iOS, follow these steps (they may vary depending on your browser version):

Go to Settings, then Safari.
Under Privacy and Security, you’ll see the Block Cookies option to adjust the type of block you want to perform.

To access your browser’s cookie settings for Android devices, follow these steps (they may vary depending on your browser version):

Run the browser and press the Menu key, then Settings.
Go to Security and Privacy, you will see the Accept cookies option to enable or disable the checkbox.

To access your browser’s cookie settings for Windows Phone devices follow these steps (they may vary depending on your browser version):

Open Internet Explorer, then More, then Settings
You can now enable or disable the Allow cookies check box.