Theory of Relativity

Theory of relativity has intrigued everyone for decades. Even to understand the theory is an arduous task. Though I have not really studied it myself, I have been awed by the impact it has had on Physics.
This morning my friend engaged me in a one-sided discussion about it. My ignorance propelled me and I just HAD to find out more about it. So here I go!
The 'Special theory of Relativity' was proposed by Einstein in 1905. This was called the 'special' theory of relativity because it considers the case where the effects of the graviation can be ignored.

Postulates of special relativity
1. First postulate
Observation of physical phenomena by more than one inertial observer must result in agreement between the observers as to the nature of reality. Or, the nature of the universe must not change for an observer if their inertial state changes.
Every physical theory should look the same mathematically to every inertial observer.
2. Second postulate
The speed of light in vacuum, commonly denoted c, is the same to all inertial observers, is the same in all directions, and does not depend on the velocity of the object emitting the light. This postulate has been verified experimentally. When combined with the First Postulate, this Second Postulate is equivalent to stating that light does not require any medium (such as "aether") in which to propagate.

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