When an image needs many hours of work, we are likely to open it, work some, save it, open it, work some, save it, etc. which brings about a substantial amount of saves. Each successive save means that a JPEG image is compressed a little more each time resulting in a loss of quality. Using Photoshop we'll assume you are after the highest possible quality levels.
So . . .
While an image is still being worked on we will use PSD to save the image.
When an image is considered to be final or finished, we'll use jpeg.
There are many other image formats around, each with a specific purpose and we'll get round to them eventually for specific applications.
The TIFF image format is also quite popular when saving an image in-between working sessions as it is also a lossless image format, but for now we'll stick to PSD's to simplify instruction.
next lesson >> 104 - Lay of the Land - Photoshop Workspace
