pulling all the books off the shelf and putting them back in place one by one. You’d put the first book in the middle of the shelf, then take the second and compare it to the first, inserting it either to the right or to the left. Picking up the third book, you’d run through the books on the shelf from left to right until you found the right spot to tuck it in. Repeating this process, gradually all of the books would end up sorted on the shelf and you’d be done. Computer scientists call this, appropriately enough, Insertion Sort.