Photoshop is a popular image editing program created by Adobe. It was first released in 1990 for Macintosh as version 1.0, with the first Windows version being 2.5 in 1992. Photoshop allows users to modify existing images and graphics through features like layers and effects. It works with bitmap images composed of pixels and is suitable for tasks like photo editing, web graphics, and more. The latest version is CC 2017 from November 2016, available on Mac and Windows.