Save Document
Save // Ctrl+S, File/ Save, File/ Save as
Common Formats you may encounter //
.PSD // Native Photoshop format, multiple layers and alpha channels
.PSB // Photoshop format for very large files (Over 30,000 x 30,000 pixels)
Output
.JPG // Compressed, usually for the web, or where a low file size is important
.TIFF // Tagged Image FIle format. High quality Print, uncompressed or lossless compressed
.PNG // Portable network graphics. Lossless compression format, 24bit RGB or 32bit RGBA
3D Render formats
.TGA // Targa, contains Single Alpha 32bit RGBA
.EXR // Open EXR, contains multiple RGB and Alpha channels, 16bit integer or 32bits per pixel floating point