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* Time is an abstraction of dates and times. Time is stored internally as

* the number of seconds with fraction since the _Epoch_, January 1, 1970

* 00:00 UTC. Also see the library modules Date. The Time class

* treats GMT (Greenwich Mean Time) and UTC (Coordinated Universal Time)_[Yes,

* UTC really does stand for Coordinated Universal Time. There was a committee

* involved.]_ as equivalent. GMT is the older way of referring to these

* baseline times but persists in the names of calls on POSIX systems.

*

* All times may have fraction. Be aware of this fact when comparing times

* with each other---times that are apparently equal when displayed may be

* different when compared.

*

* = Examples

*

* All of these examples were done using the EST timezone which is GMT-5.

*

* == Creating a new Time instance

*

* You can create a new instance of time with Time.new. This will use the

* current system time. Time.now is a synonym for this. You can also

* pass parts of the time to Time.new such as year, month, minute, etc. When

* you want to construct a time this way you must pass at least a year. If you

* pass the year with nothing else time with default to January 1 of that year

* at 00:00:00 with the current system timezone. Here are some examples:

*

* Time.new(2002) #=> 2002-01-01 00:00:00 -0500

* Time.new(2002, 10) #=> 2002-10-01 00:00:00 -0500

* Time.new(2002, 10, 31) #=> 2002-10-31 00:00:00 -0500

* Time.new(2002, 10, 31, 2, 2, 2, "+02:00") #=> 2002-10-31 02:02:02 -0200

*

* You can also use #gm, #local and #utc to infer GMT, local and UTC

* timezones instead of using the current system setting.

*

* You can also create a new time using Time.at which takes the number of

* seconds (or fraction of seconds) since the Unix

* Epoch[http://en.wikipedia.org/wiki/Unix_time].

*

* Time.at(628232400) #=> 1989-11-28 00:00:00 -0500

*

* == Working with an instance of Time

*

* Once you have an instance of time there is a multitude of things you can do

* with it. Below are some examples. For all of the following examples, we

* will work on the assumption that you have done the following:

*

* t = Time.new(1993, 02, 24, 12, 0, 0, "+09:00")

*

* Was that a monday?

*

* t.monday? #=> false

*

* What year was that again?

*

* t.year #=> 1993

*

* Was is daylight savings at the time?

*

* t.dst? #=> false

*

* What's the day a year later?

*

* t + (60*60*24*365) #=> 1994-02-24 12:00:00 +0900

*

* How many second was that from the Unix Epoc?

*

* t.to_i #=> 730522800

*

* You can also do standard functions like compare two times.

*

* t1 = Time.new(2010)

* t2 = Time.new(2011)

*

* t1 == t2 #=> false

* t1 == t1 #=> true

* t1 < t2 #=> true

* t1 > t2 #=> false

*

* Time.new(2010,10,31).between?(t1, t2) #=> true