Should be in all caps, since they are constants
Is considered regular calendar and time
Length is described as periods
Is a timeline measured in nanoseconds
Time after the epoch is positive
Can be used in formal parameter list of a method
Beginning is referred to as the epoch (1/1/1970)
Can be used in switch statements
Good examples would be months of the year, days of the week, etc
Time before the epoch is negative
Useful for defining a set of pre-defined, related constants
Length is measured as Duration
Consists of units like years, months, day, hours, minutes, seconds
