The document compares the 12-hour clock system and the 24-hour clock system. The 12-hour clock uses a.m. and p.m. designations, while the 24-hour clock runs from 00:00 to 23:59 without those designations. Examples show that 07:00 p.m. on a 12-hour clock is equivalent to 19:00 on a 24-hour clock, and that 05:10 p.m. and 06:15 a.m. on a 12-hour clock are equivalent to 17:10 and 06:15, respectively, on a 24-hour clock.