Have you ever noticed how your computer knows which program to open when you double click on a file? It doesn’t always know but most of the time it does. When it doesn’t know, your ...

You can identify a file's format by its extension, which appears at the end of the file name, such as .doc for Word documents or .png for images (PNG stands for Portable Network Graphics).

Starting with Microsoft Office 2007, Office Open XML is the default document format for saving applications. See Office file formats and ECMA. An Office Open XML (OOXML) document is a zipped ...