### Theory:

Step 1: If the given time is $$00\!:\!00$$ hours (midnight), then change $$00\!:\!00$$ hours as $$12\!:\!00$$ a.m. and proceed further. There is no change up to $$12\!:\!59$$ p.m.

Step 2: If the given time is $$01\!:\!00$$ hours to $$12\!:\!59$$ hours, then no time change in $$12$$-hour format. Just write the time as it is and mention a.m. at the end of the time up to $$12$$'O clock, mention p.m. at the end of the time after $$12$$'O clock.

Step 3: If the given time $$13\!:\!00$$ hours to $$23\!:\!59$$ hours, then subtract $$12\!:\!00$$ hours from the given time and write p.m. at the end of the time.
Example:
1. Convert $$00\!:\!30$$ hours to $$12$$-hours format.

Solution:

By using the above procedure, change $$00\!:\!00$$ hours as $$12\!:\!00$$ a.m.

Therefore, $$00\!:\!30$$ hours $$=$$ $$12\!:\!30$$ a.m.

2. Write $$06\!:\!20$$ hours in ordinary format.

Solution:

$$06\!:\!20$$ hours lies between $$01\!:\!00$$ hours to $$12\!:\!59$$ hours.

By the above procedure, no time change between $$01\!:\!00$$ hours to $$12\!:\!59$$ hours.

$$06\!:\!20$$ hours means morning, so mention a.m. at the end of the time.

Therefore, $$06\!:\!20$$ hours $$=$$ $$6\!:\!20$$ a.m.

3. Convert $$22\!:\!10$$ hours to $$12$$-hour format.

Solution:

$$22\!:\!10$$ hours lies between $$13\!:\!00$$ hours to $$23\!:\!59$$ hours.

Subtract $$12\!:\!00$$ hours from the given time by the above procedure.

$\begin{array}{l}\phantom{\rule{0.588em}{0ex}}22:10\\ \underset{¯}{-12:00}\\ \underset{¯}{\phantom{\rule{0.588em}{0ex}}10:10}\end{array}$

$$22\!:\!10$$ hours means night, so mention p.m. at the end of the time.

Therefore, $$22\!:\!10$$ hours $$=$$ $$10\!:\!10$$ p.m.