Do you spend hours and hours working in Photoshop? If so, you can save loads of time by using shortcuts. Even learning and using just a couple of shortcuts can increase your efficiency and productivity by hours over time. Here is a very thorough article on keyboard shortcuts by Tom Giannattasio. It’s loaded with illustrations and is definitely worth bookmarking.
There is also a goldmine of information about keyboard shortcuts in the online Photoshop Help. Check out these two items:
If you are already using shortcuts and wonder about some of the reasoning behind the shortcut changes in Photoshop CS4, you should read John Nack’s blog post about it called, Shortcut changes in PSCS4.