USB webcams are great to capture images and videos. Raspberry Pi supports most USB webcams.
To be on the safe side, go through the list of supported webcams by Pi at http://elinux.org/RPi_USB_Webcams.
I am using a Logitech HD c310 USB webcam.
You can purchase this webcam from Amazon, and you can find the product details at http://www.logitech.com/en-in/product/hd-webcam-c310.
Attach your USB webcam to Raspberry Pi through the USB port on Pi and run the
lsusb command in the terminal. This command lists all the USB devices connected to the computer. The output should be similar to the following output, depending on which port is used to connect the USB webcam:
pi@pi02 ~/book/code/chapter02 $ lsusb Bus 001 Device 002: ID 0424:9514 ...