Most computers have a number of indicator, or activity, lights on the chassis. These tiny light-emitting diodes indicate that a certain component is active. They monitor activity of such things as power into the system or memory card acquisition. Most indicator lights will blink if the activity of the component is intermittent, such as with a memory card. These lights are particularly helpful in preventing mistakes such as removing a |floppy diskette| from its |drive| while the computer is accessing it (which is likely to damage the disk).
