.SITX files are associated with the 'StuffIt' family of archiving and compression utilities. 'StuffIt' utilities are available for use within the Apple Macintosh, Microsoft Windows and Linux platforms.

'StuffIt' was originally created by 'Raymond Lau' in 1987, and was marketed by the company 'Alladin systems' now known as 'Allume systems', The file extension .SITX is associated with the utility 'StuffIt X' which was released in 2002 and offered 20% further compression compared to the original 'StuffIt' utility.

Later versions also include 15-30% compression of JPEG images.

At the time of writing this the benefits of using 'Stuffit' over utilities such as 'Winzip' include:

* Able to compress JPEG's with no loss of quality.
* Can compress and burn direct to CD/DVD.
* Protection against data corruption.
* Search for files within .zip, .sitx archives by name, date, and more

Drawbacks:

Due to the increased popularity of built-in operating system utilities such as ZIP computer users are less and less likely to possess the software required to decompress a .SITX (or.SIT) file. Which has lead to software developers and distributors being reluctant to release software compressed in this format.