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How to put an image in the URL address of your page.

What you want to put on your page is a favicon (short for 'favorites icon'), also known as a website icon, a page icon or an urlicon.
Any sixteen by sixteen or larger image will do as long as it is an
image format supported by the web browser (normally)
How to get a real ico image? The HTML KIT website has an automatic converter 
FavIcon from Pics -- favicon.ico for your website
It is quite fun. You can use an image that you find with google or all the web images or make your own pic using gimp.
Gimp comes in many flavors there is gimp for windowsgimpshop which is more like photoshop or psp and you can even get gimp portable
which fits inside your usb key and does not have to be installed on each computer you visit.
Once you have chosen or created your image upload it to
FavIcon from Pics   and download the resultant favicon.ico
It is easier to then put the image in the same folder as your page.

Then you need to write a little code.
When using a typical urlicon with the suffix .ico: you will need to put this in the <HEAD> section of your page:

<link rel="shortcut icon" href="favicon.ico">

BTW you do not have to name your icon
favicon.ico and you can write the entire url of your  favicon.

However, if you want to be more precise:
<link rel="shortcut icon" href="http://example.com/favicon.ico" type="image/vnd.microsoft.icon">
As you may have guessed the ico format originated with Microsoft.
Being precise seems to be important if you are going to use png or animated gifs for example.
<link rel="shortcut icon" href="http://example.com/favicon.ico" type="image/png">
<link rel="shortcut icon" href="http://example.com/favicon.ico" type="image/gif">

As usual have fun with this. Remember to be meticulous!  A missing  point or quotation mark will ruin everything.
BTW the page icon that I used was a jpg and its location is here.