Fish is daily protein source for 1.2 billion people, but fishers are more and more frequently returning home with empty nets. Watch this amazing animation and find out how you can help prevent overfishing.
If you don't have installed program for editing PDF documents on your computer, then you can use web application PDFescape which allows you to edit your documents in your browser.
Often in PHP you want the same block of code to run over and over again and instead of adding several almost equal lines, you can use loops to perform this task much easier.