Interlaced

Glossary

Interlaced

When you watch television, you're looking at an interlaced video display. On TVs as on computer monitors, the whole screen is drawn line by line. But because early television tubes couldn't draw the whole screen before the top began to fade, TV engineers implemented a system called interlacing, which skips every second line on the first pass and fills in those lines on a second pass.

This system might result in a little flicker, but it avoids having the bottom of the screen perpetually brighter than the top. It also gets away with refreshing the screen half as often. Most normal-resolution PC and Mac monitors aren't interlaced, but lower-quality display adapters pushed into high resolutions and high color sometimes do interlace. It's not a pretty sight up close, however. Avoid it when you can.