The sort command is a simple database tool. It allows you to specify the field to be sorted on and the type of sort to be carried out on it. sort filename . Lines are sorted into the following order: lines starting with numbers come first, followed by lines starting with upper-case letters, which are followed by lines starting with lower-case letters and finally symbols such as % and ! ... Saving the results of a sort to a file . Checking if a file has been sorted . ...