The ability to tell time in a common international language is an intregal part of the Amehrihkn language. Professional people, doctors, scientists, businesses and the military all use the 24hr. clock.

Each day starts at midnight (0000hrs) and goes 24 hrs ending at midnight(2400hrs.).
Here's how we read it. 0100 is 1:00am, 1305 is 1:05 pm which actually means it is 13 hrs and 5 min. past midnight.

Here's the 24hr clock vs. the 12hr clock:

24hr clock ......................................12hr clock

0000 .................................................. 12:00am
0100 .................................................. 1:00
0200 .................................................. 2:00
0300 .................................................. 3:00
0400 .................................................. 4:00
0500 .................................................. 5:00
0600 .................................................. 6:00
0700 .................................................. 7:00
0800 .................................................. 8:00
0900 .................................................. 9:00
1000 .................................................. 10:00
1100 .................................................. 11:00
1200 ...................................................12:00pm
1300 .................................................. 1:00
1400 .................................................. 2:00
1500 .................................................. 3:00
1600 .................................................. 4:00
1700 .................................................. 5:00
1800 .................................................. 6:00
1900 .................................................. 7:00
2000 .................................................. 8:00
2100 .................................................. 9:00
2200 .................................................. 10:00
2300 .................................................. 11:00
2400 .................................................. 12:00 am

What time would it be on the 12hr clock if it is 1500hrs on the military clock?
Without the aid of the chart above you can figure it out in your head this way.
You subtract 12 o'clock noon from any military time past noon,so 1500 - 1200= 3:00pm.
To calculate it vice-versa add 3:00pm to 1200=1500hrs on the 24hr. clock