Information

Place the cursor one position to the left. This operation may erase the character that is placed leftwards of the cursor in output. Before discussing the output, let's remember some history. If you printed the character in early computer technology you couldn't erase it, so in output backspace was sometimes used in the function of generating accented characters in ASCII. Let's see: à could be produced using the three character sequence a BS ` (or, using the characters' hex values, 0x61 0x08 0x60). Nowadays this thing is widely criticized and not supported at all. In order to get rid of any ambiguity between the two possible uses of backspace, programmers decided to make a cancel character control code a part of the standard C1 control set.

Let's move on to the backspace. It is a keyboard key with the initial function of pushing the typewriter carriage one position backwards. Nowadays in modern computer systems backspace moves the display cursor one position backwards, deletes the character at that position, and shifts back the text after that position by one position.

Typewriter

In some typewriters there was a long system of typing. Let's see an example. How could a typist create a lowercase letter A with acute accent (á). First he or she had to type a lowercase letter A, press backspace, and then the acute accent key. This method is also called an overstrike. It is the basis for such spacing modifiers in computer character sets such as the ASCII caret (^, for the circumflex accent). Nowadays backspace composition is out of use with typical digital displays or typesetting systems that we use nowadays. We can say that it was partially replaced with the combining diacritical marks mechanism of Unicode, despite the fact that such characters don't perfectly work with lots of fonts. That's why the precomposed characters continue to be used. There is an opposite method for diacritical marks, which is used by some software (like TeX or Microsoft Windows). It is the following: namely positioning the accent first, and then the base letter on its position.

Computers

Everybody knows what does the term "backspace" means, as well as knows its primer function: to delete the character to the left of the cursor. However, the actual key may be called in many different ways, for example delete, Erase (for example in One Laptop Per Child), or with a left pointing arrow. A special symbol for "backspace" exists as U+232B ⌫ but its use as a keyboard label is not universal.

The backspace and the delete key are two different keys. In paper media for computers the delete key would knock out all the holes to cross out a character. In nowadays computers deletes text following it. Besides, the delete key has one more function: it frequently works as a generic command to remove an object (for example an image inside a document, or a file in a file manager), while backspace usually does not.

Common use

The backspace key is often matched to the delete character (0x7f in ASCII or Unicode) in modern systems. However, the backspace primer function, deleting the character before the cursor, remains.

The backspace key is usually used to go back a page or up one level in graphical web or file browsers.

Hash

MD5 Backspace

SHA256 Backspace

Base64 Backspace

• ← Previous char 'BEL', code: 7
• Next char 'HT', code: 9 →

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