Backspace is a key on a computer keyboard that deletes the character immediately to the left of the cursor. When you're typing and notice a mistake, you press backspace to erase it, one letter at a time. The cursor moves backward as it removes each character, like an eraser that works in reverse.

Before computers, typewriters had a backspace key too, but it only moved the carriage backward without erasing anything. You'd have to type over your mistake or use correction fluid. Modern backspace makes fixing errors much simpler: just hold it down and watch your mistakes disappear.

The word can also be used as a verb. If you accidentally type “teh” instead of “the,” you might backspace twice to delete the “eh” and then retype it correctly.

On some keyboards, backspace is labeled with a left-pointing arrow. On phones and tablets, the equivalent key often shows an X or a delete symbol. Different devices handle it slightly differently, but the basic idea remains the same: backspace deletes what you just typed, giving you a quick way to correct mistakes without starting over.