The term archive is usually used to refer to a set of files stored in one folder or under a certain classification, to eventually transfer to another hard drive or location. This becomes especially useful when too much information has been stored on one computer, and a percentage of this is still useful enough to keep but not needed for immediate use.
Certain programs can make archiving easier for users. For instance, the program WinZip allows users to store a large number of files in one archive for easier sending. Since WinZip compresses files in order to facilitate quick transfers, it also enables the recipient to extract the compressed files for normal use.
In email providers such as Gmail, however, archiving is a process in which the user creates another label or folder then moves certain emails to that folder. This enables the user to free up the inbox, making it less cluttered. It also serves to organize the many emails one receives according to topic or use.
In blogs, archives store blog entries which were posted in the past. The blog can classify posts according to month or year. Posts may also be classified according to topic, or more specifically, to tags. Tags belong to a set of themes that users may assign to their posts. When looking for old posts which all under a similar category, the reader can simply search for all posts with a certain tag.
The same is often true for online magazines and other online publications. Old releases may be stored in archives and placed under certain categories for easier access.