Photoshop 2.0

(Mac OS) You can use this format to open an image in Photoshop version 2.0 format or to export an image to an application supporting only Photoshop 2.0 files. Saving in Photoshop 2.0 format flattens your image and discards layer information.

Saving Images > Saving images in specific formats > Photoshop 2.0