ZAP file is a text file used in Windows operating system. This format is a rather limited counterpart of the more popular MSI file format. ZAP file structure is divided into two main parts: header and instructions for the installer.

One of the main flaws of ZAP format is lack of autostart function and limited capabilites regarding restoring changes made in situations where the application installation process was incomplete or faulty. On the other hand, ZAP file have the advantage of not needing administrative privileges to execute contained code.