OnlineGDB is described as 'com is an online compiler and debugger tool for C/C++. Code, compile and run program in browser and debug program with command line gdb debugger online itself' and is a IDE in the Development category. There are three alternatives to OnlineGDB, not only websites but also apps for. The best alternative is Ideone, which is free. Other great sites and apps similar to OnlineGDB are Coding Ground (Free) and codepad (Free).
Compile and Execute your favorite programming languages online, click any of the following to proceed! Web Technologies, Text Formatting, Useful Utilities, Programming Languages. Vim, emacs modes are avaliable.
Very simple webpage with a simple textbox, a checkbox for selecting one of several languages and an option to make it private and to run the code or not. Has a little code sharing and references as well.