sorting

In computing, arranging data in sequence. When sorting a collection, or file, of data made up of several different fields, one must be chosen as the key field used to establish the correct sequence. For example, the data in a company's mailing list might include fields for each customer's first names, surname, address, and telephone number. For most purposes the company would wish the records to be sorted alphabetically by surname; therefore, the surname field would be chosen as the key field.

The choice of sorting method involves a compromise between running time, memory usage, and complexity. Those used include selection sorting, in which the smallest item is found and exchanged with the first item, the second smallest exchanged with the second item, and so on; bubble sorting, in which adjacent items are continually exchanged until the data are in sequence; and insertion sorting, in which each item is placed in the correct position and subsequent items moved down to make a place for it.