Carry (arithmetic)

It is part of the standard algorithm to add numbers together by starting with the rightmost digits and working to the left.

Such omissions were criticized by such groups as Mathematically Correct, and some states and districts have since abandoned this experiment, though it remains widely used.

[1][2][3][4] In abstract algebra, the carry operation for two-digit numbers can be formalized using the language of group cohomology.

[8][9] Carry represents one of the basic challenges facing designers and builders of mechanical calculators.

Another challenge is the fact that the carry can "develop" before the next digit finished the addition operation.

Another notable machine using similar method is the highly successful 19th century Comptometer, which replaced the weights with springs.

When speaking of a digital circuit like an adder, the word carry is used in a similar sense.

Normally, a carry bit value of "1" signifies that an addition overflowed the ALU, and must be accounted for when adding data words of lengths greater than that of the CPU.