Einstein's theory of relativity can be divided into two different cases
- Special theory of relativity
- General theory of relativity
The premise of the former is a prediction that mass can be directly converted to energy, a theory which serves as the base principle for atomic bombs and can be referred to as a special case. Special case simply meaning the absence of gravity.
The general theory is the same only this time gravity is present which is the norm.
The relativity theory helped in making tons of advancement in the concept of space and time at the time of its discovery and if not for this theory the field of astronomy would not have advanced to the point where men would have landed on the moon.
Special relativity helps to figure out how space and time is structured. Perhaps the most notable resultant theory of special relativity is the famous equationE = mc2 , also known as the mass-energy equivalence
General relativity basically explains gravity and why some bodies contain more gravitational pull than the others. General relativity thoery claims that two parallel bodies have an existing gravitational force that pulls them towards each other, something like a tug of war, the body with the most mass of the two bodies would be the most dominant one which which end up winning the tug of war pulling the first body close to it.