Buy the right webcam

A webcam is an image capture device that is connected to your desktop pc or notebook computer usually through a USB cable. Some webcams may use the older USB 1.1 standard which allows a maximum data transfer of only 12 MBit/s that limits the quality of video capture. If the video quality is important for you, then you should go only for webcams that use the USB 2.0 standard, where maximum data transfer is 480 Mbit/s, which is more than enough for a webcam.

Webcam Design

Webcams come in different shapes and forms. Some of them are special designed for notebook computers and have a clip for attaching them on the notebook screen. This clip may not be suitable for your desktop screen which is usually wider. Others are simply made to sit on desks.

Video quality - Resolution and Frame Rate

If you want a high video quality you should consider high resolution and a high frame rate like 30 frames per second.
There are cameras that support a resolution of more than 1 MP (megapixel) which is high enough for our times. A lower resolution, like 640 x 480 pixels (VGA) would be just fine for basic video conferencing.

Lens - Focus and Zoom

The most webcams come with fixed focus, while others come with manual focus adjustment or even auto focus. Focusing on an object will make that object appear more clear.
Unfortunately regular webcams do not have optical zoom and offer only digital zoom.

Other specs

Webcams can come with an incorporated microphone.
For dark areas, some webcams have built-in leds that can be switched on manually, or automatically by a sensor.
Most cameras are automatically recognized by the computer and you don't need to install any software. However, you may need software if you plan to use the webcam for video surveillance, video conferencing, video instant messaging and other activities.

After you have read all this information you can start searching for cheap webcams