Zip File (*.zip)

Zip files contain one or more original files that have been compressed? into a smaller size, usually to decrease transfer speeds over the internet.

Before the original contents of a .zip file can be accessed, they must first be decompressed or "unzipped" (see below).

Unzipping (decompressing) files

Both Windows XP and Mac OS X have built-in support for unzipping files. In either case, simply double-click the zipped file icon and drag any of the contained files to a desired location (frequently your desktop).

Zipping (compressing) files

Zipping files can be very useful, especially if you're sending a bunch of small files (e.g. pictures) over the internet, since the zip file will consolidate them into one, easy-to-handle file. Compressing files can also be useful when backing up your data if you're crunched for space.

Windows XP | Mac OS X

Windows XP

There are two ways to create a zip file in Windows:

1. Right-click on your desktop (or wherever it is you want to put the .zip file) and select New > Compressed (zipped) Folder. Name it whatever you want, and then drag whichever files you want compressed on top of the zipped folder (the folder should become highlighted when you do this). Depending on the size of the file(s), it may take a few seconds to compress your data down to a smaller size.
2. Select all the files you want to zip (using either SHIFt- or CTRL-click). Once this is done, right-click on one of them and select Send to > Compressed (zipped) Folder. A zipped folder should appear after a few seconds with compressed copies of all your files. Note that you can still drag and drop files in and out of this folder if you later change your mind as to which files you wanted to compress.

Mac OS X

In OS X, simply CTRL-click on whichever file or folder you wish to compress and select Create Archive of "<filename>". A compressed copy should appear next to the original in a few seconds. Note that you can still drag and drop files in and out of the compressed folder if you later change your mind as to what you wanted to compress.