Backspace

Backspace is a key on computer keyboards and a control character used to delete text to the left of the insertion point. In normal use, pressing Backspace removes the character immediately before the cursor or deletes the currently selected text.

Historically, the concept derives from typewriters, where a backspace mechanism moved the carriage one position to the left and often erased the previous character with a masking ribbon. As keyboards and computer interfaces evolved, the Backspace key retained the ability to remove preceding characters, becoming a standard editing tool in text input fields, word processors, and command-line interfaces.

Technically, Backspace corresponds to the control character BS, historically encoded as ASCII 08 and Unicode U+0008. In practice, its visible effect depends on the application and terminal or editor in use. Most text editors delete a single character to the left, and if a text region is selected, Backspace removes the selection. Some programs support enhanced behavior, such as deleting a word or line when combined with modifier keys or when used in particular editing modes.

Variations across platforms include how the key is labeled and mapped. On many Windows and Linux keyboards, Backspace is a dedicated key separate from Delete, which removes characters to the right. On Apple keyboards, the key labeled Delete often performs the backspace function, while Forward Delete is produced by a different key combination (such as Fn+Delete on compact keyboards). In terminals and command shells, the key may emit different codes (such as 0x08 or 0x7F) depending on the system and software.

In summary, Backspace is a foundational editing control for removing preceding text, with a long historical lineage and behavior that is largely consistent across software, though platform-specific variations exist.