time conversions: application exercise

Time units are measurements used to express the duration of events, periods or intervals. Below are the most common units of time:

Fundamental units of time
1. *Second (s)*: It is the fundamental unit of time in the International System of Units (SI).
2. *Minute (min)*: It is equal to 60 seconds.
3. *Hour (h)*: It is equal to 60 minutes or 3600 seconds.
4. *Day (d)*: It is equal to 24 hours or 86,400 seconds.

Larger units of time
1. *Week (s)*: It is equal to 7 days.
2. *Month (m)*: It is a period of time that varies between 28 and 31 days.
3. *Year (a)*: It is equal to 365 days in a common year and 366 days in a leap year.
4. *Decade*: It is equal to 10 years.
5. *Century*: It is equal to 100 years.
6. *Millennium*: It is equal to 1000 years.

Minor units of time
1. *Millisecond (ms)*: It is equal to one thousandth of a second.
2. *Microsecond (μs)*: It is equal to one millionth of a second.
3. *Nanosecond (ns)*: It is equal to one billionth of a second.
4. *Picosecond (ps)*: It is equal to one billionth of a second.

Other units of time
1. *Light year*: It is the distance that light travels in one year, approximately 9,461 trillion kilometers.
2. *Astronomical century*: It is equal to 100 years, used in astronomy to measure long periods of time.