Files with the .HTA extension contain HTML code and possible script code in VBScript or JScript language and can usually be run in a web browser window. HTA files in Windows are executed by the Microsoft HTML Application Host - Mshta.Exe - after double-clicking them.

If the HTA file is on the Internet, the browser usually provides a dialog asking if you want to run or save the file. An HTA file can be created by changing the file extension from .HTM to .HTA.