Why is backspace often represented with ^H?

Question

I don't see what ^H has in common with "backspace". Why is backspace represented that way in many locations?

Answer 1

^ represents holding the Ctrl button. With any of the characters from @ to _, it generates a character 64 (0x40) positions earlier in the ASCII table.

Answer 2

See http://en.wikipedia.org/wiki/Caret_notation - ^H simply means 0x08 because H is the 8th letter of the alphabet. There's nothing linking this to the backspace functionality except the fact that 0x08 was assigned the BS function code. It could just as easily have been 0x09, then we'd be writing ^G.

Answer 3

"This sequence is still used humorously for epanorthosis by computer literates, denoting the deletion of a pretended blunder, much like a strikethrough."

"My slave-dri^H^H^H^H^H^H^H^H^Hboss decided to stall the project."

Backspace - Wikipedia

@Matt - Queue the old folks, haha!

Answer 4

This is because of where it comes in the ASCII table, there is no significance it's assignment to H other than that's the order in which controls were assigned to the ASCII charachters.

See this wiki on ASCII; ASCII Explained

It appears so frequently in computing due to the commonality of ASCII and it's extensive use.

Answer 5

The actual answer is much simpler and non-arbitrary. HJKL is how you navigate in most command line editors, rather than using the arrow keys. H is the equivalent of the left arrow key (with JKL being down, up, and right, respectively). So you could use H to move the cursor back one character or ^H to delete one character back.