What's the logic behind changing an IP address?

[KTD]

Please don't laugh.... I'm a newbie to lots of this techy stuff and to this site. I stumbled upon the forum topic of how to change an IP address. I found it fascinating, but am a bit confused why one would even need/want to change it. Maybe I'm not using my computer to its full potential. Do I get any "techy points" for conducting the Speed Test on my own?

[AboveTheLogic]

You IP identifies you on the Internet. Once someone has your IP they can scan for vulnerabilities and try to get into your system, track your general location, find out who your ISP is, etc.

If you get banned from a forum or a game, or want to simply appear as a different person (say you want to circumvent the download limitation on rapidshare), changing your IP might just be the ticket...

[aziernest]

Another reason / logic behind changing the IP address includes changing country of origin.

Let's say an IP-Range of Pakistan, has been blocked to view blogspot.com so a pakistani visitor may like to change his ip to bypass the restriction impled on the whole country range.