Expand may refer to any of the following:
1. The process or opening a folder and displaying all its contents. For example, with Microsoft Windows, in Explorer, a user may click the plus ( + ) symbol next to a folder or double-click it to expand and view its contents. If you wanted to hide its contents, click the minus ( - ) to collapse the folder.
2. The process of taking a compressed file and extracting all the files. This restores the files to the original format.