Why when i put my sd card from my digital camera, nothing happens...i cant seem to download my pics how can i?

You should check if you had put it in in the correct place it might fit but if the space it the correct one the data can't be inserted into the computer.

Go to (control panel, then system, then go to the hardware tab). In the hardware tab you will see a button called device manager. Once in device manager (I would have your camera unplugged from the computer) - then replug the camera in while watching device manager. If it doesn't auto find the hardware you can go to the (top-little pc monitor looking thing) and highlight it, then go to your "actions" tab and hit "scan for hardware changes". That forces the PC to look for new devices such as flash drives, printers, cameras etc... 90% of the cameras will not need a driver installed for XP or Vista to use them. If not, it will come up a yellow (!) explanation mark beside the new hardware. That will tell you it needs to go to the camera's manufacturer website and download the drivers for it. If it does find it while your monitoring that device manager page you will see a new device come up and you can double click over it after expanding the (+) sign and look to see if it found your camera. Also, alot of cameras will show up under mycomputer as a drive letter, sort of like a memory stick from a camera or cell phone.