Every Twitter user is identified by its unique Twitter URL (For example, TechF5 has twitter URL twitter.com/techf5). Any Twitter user can change this username URL as per requirement. After the change, your Twitter username URL will change and rest everything including tweets, friends etc will remain the same.
Steps to change Twitter.com username URL
1. Goto Twitter.com & login into your account.
2. Click Settings link at top right.
3. Under â€œAccountâ€ tab you can change Twitter username. You can enter any username provided it does not have spaces or is not being used by any current Twitter user.
4. Click Save button after entering new username for your Twitter account. New username URL may take some time to refresh throughout Twitter website.