This article describes what ZIP files are and why they're used in some situations. We'll also look at how to open one to see its contents, and how to convert the files inside to a different format ...

At the top, you will find three main options—Add, Convert, and Extract. Selecting the Add option allows you to archive files, ...

This free Web service does one thing and does it well: changing your file formats instantly with no hassles.

But even free Zamzar is pretty quick, and incredibly convenient when you want to convert a file without messing around with software.

When it comes to converting file extensions on your iPhone, don't worry about downloading a third-party app when you can make the changes yourself.