what is <link rel="icon" type="image/x-icon"> used for?

Question

I am trying to create a website and I have been looking at coded websites that are currently uploaded and that has appeared and I have never seen it before.

Could someone please explain what it is for and if I need it or not?

Answer 1

It defines this little picture which is commonly called the "favicon". Its that little icon on the left side of a tab or a browser window:

But the tag you wrote in your question doesnt affect anything because its missing a reference to the icon itself: href="favicon.ico".