What is your IP? | ViewIP.info
IP Lookup, IP WHOIS, IP Address Checker
Displays your current IP address
Find your IP address here!
Are you in the Cloud? HostCheetah.com
See How Fast Your Connection Is
Speedtest.net is a free broadband connection analysis website founded by Ookla Net Metrics in 2006. Users can test their internet speed against hundreds of geographically dispersed servers around the world.

At the end of each test, users are presented with their download (the speed of data from the server to your computer) and upload (the speed of sending data from your computer to the server) bandwidth speeds.

The tests are performed completely within your web browser over HTTP (just like normal web browsing). Since its inception, well over 1 billion speed tests have been conducted on Speedtest.net.
Wikipedia
What is IP Address?

An Internet Protocol (IP) address is a numerical label that is assigned to devices participating in a computer network that uses the Internet Protocol for communication between its nodes.

An IP address serves two principal functions: host or network interface identification and location addressing. Its role has been characterized as follows: "A name indicates what we seek. An address indicates where it is. A route indicates how to get there."
Wikipedia