What is Adobe Photoshop?
Adobe systems had developed and published a raster graphics editor for Windows, which was termed as Adobe Photoshop. John Knoll and Thomas are the ones who created it in year of 1988. An Adobe Photoshop can help in composing and editing of raster images in several layers. It also supports multiple color models that include CMYK, RGB, CIELAB, duotone and spot color. An Adobe Photoshop uses .PSB and .PSD file formats for all the features but it does support the graphic file format too. The .PSD extension stands for Photoshop Document and usually these files have 2GB size with maximum 30,000 pixels. The second file extension .PSB that stands for Photoshop Big is used for document format which are large.
If you want to expand the number of features offered by a Photoshop then you can use Photoshop plug-ins for experiencing the enhanced features of the software.