As someone who is the WORST at comprehending anything related to science, let alone explaining scientific material like this, this article is written in a semi-simple and almost painless way for people with limited intelligence like me.
So the theory of relativity is a very profound theory formed in 1905 by the one and only, Albert Einstein. This man single-handedly proposed new concepts of space and time. It is the notion that the law of physics are the same to all observers everywhere. It overall explains way more than what that boy Newton came up with his 3 laws of gravity.
The theory of relativity was based on two principles, the principle of relativity and the principle of the speed and light. The first principle states that the law of physics don’t change, even for objects moving in inertial (constant speed) frames of reference. Einstein deduced that there is no fixed frame in the universe and that everything is moving relative to everything else. This is known as special relativity since it applies only to frames of reference in constant, unchanging motion. The second principle states that the speed of light is the same for all non-accelerating observers within a vacuum, regardless of their relative motion to the source of light.
Being the genius that he is, Einstein essentially created a fundamental link between space and time through his mathematical equations. The formula E=mc^2 expresses the fundamental relationship between mass and energy, which is what we use to approach the speed of light. The universe can be viewed as having three space dimensions (up/down, left/right, forward/backward) and one time dimension. Therefore, space-time must be a 4-dimensional object which is called a space-time continuum. Continuum refers to the fact that space and time has no apparent limit in size or duration.
Throughout his research, Einstein realized that gravity is basically warped space and time and that massive objects, like the sun and the earth, cause a distortion in it. This describes the history and expansion of the universe, the motion of the planets, bending of light, and the existence of black holes. Einstein’s theory of relativity is the key to understanding the cosmos.
Hopefully this blog makes sense and if it doesn’t there are other sources out there that do a much better job at explaining what Einstein’s theory of relativity is. In fact, this blog should be the last source you should use to learn about what the theory is. It probably would have been better to not have read this.