Understanding of Adobe Photoshop CS4 Tools

After having troublesome of installing Adobe Photoshop CS4 which I finally able to install it, I search in google to find out more details about Adobe Photoshop, the usage and the way how to play with the tools to edit pictures. Finally, I managed to learn the introduction of Adobe Photoshop. I able to understand the tools because I have exposed myself in Adobe Photoshop 7 before. So, after understanding the each tool's function, I able to recall how last time I use the tools to edit my images. This is the URL of the web which I learn of how to play with Adobe Photoshop... http://photoshopgurus.com/tutorials/t007.html.