How do you activate your account with URL?

First you must be somewhat familiar with databases.

After a user creates an account, the row in the table that corresponds to the new user needs to have at least three attributes: a unique id, a username, and a flag (usually 1 or 0 for active and inactive).

The user then gets sent a link via email such as:

www.mysite.com/activate.php?UNIQUE_ID=123456789&USERNAME=tomjones@Yahoo.com

Here you can see that the script will be passed the UNIQUE_ID and USERNAME.

When the user clicks it, the database matches the unique id AND user id to the row entry in the database and changes the flag so that account is now active.

Hope this helps.