How to explain general relativity in a simple and intuitive way?

Although the general relativity theory is regarded as one of the most beautiful ideas in nature, it is often seen as an obscure topic. If you are finding a simple and intuitive explanation of General Relativity, this video is for you.
Albert Einstein presented Special Relativity theory in the early 1900s. However, he was not happy with the concept, as it didn't apply to situations where gravity was present, or the observer was moving faster.
As a brief introduction, General Relativity is the most accurate theory of gravity so far. General Relativity explains gravity as a property of spacetime rather than a force, namely, as the curvature of spacetime, which is caused by matter and energy.
Let's imagine the phenomena below to visualize General Relativity easily.
Let's say that you're on earth and pointing a flashlight straight from one side to the other. You will find that the height of the light measured on the wall is even with the height of the light's source. It means that light goes straight to the other side of the room.
However, if you do the same experiment on a spaceship and it is accelerating upwards. You will find that the height measured on the wall would be lower than the light's source. It is explained as the floor of the room would be rushing upwards at ever faster speeds as the light propagated across the room. The light beam would appear to curve downward.
When it comes to light, the light should be traveling on the shortest path possible. However, Einstein eventually realized that the light's shortest path might be a curved line near gravity instead of a straight line. Gravity and acceleration were different methods of describing the same phenomena. The idea of acceleration was used to connect gravity in the theory of relativity, and this became the basis of General Relativity
This was a key insight that Einstein had when it came to gravity. In order to get this mathematical insight, he had to resort to complicated mathematics. He then contacted Marcel Grossman, a mathematician from his college days to gain his support.
To properly take this theory seriously, Einstein had to make a prediction that would be tested. His prediction was able to explain the mysterious nature of Mercury's orbit, which had been a mystery for several decades. General Relativity predicted exactly the precession that Mercury actually has.
Many skeptics still doubted Einstein's prediction. However, four years after he published the theory, Arthur Eddington, an astronomer, and his team were able to prove it. They were able to show that the light from the sun was bent due to its gravity with a photograph of stars near the sun during a total solar eclipse. This was the moment when Einstein became a celebrity.
There is not just a distortion of space but also of time. Due to the curvature of space, the distance that light travels in a gravitational field is longer than in an empty space. This means that time passes slower in a gravitational field compared to that in an empty space.
Special relativity compared to General relativity.
The special relativity equations are basically sets of equations that describe how things look in different frames of reference. The stretching of time and space and the increase in mass.

General relativity is more complicated. It describes the relationship between mass and the curvature of space, and the dilation of time. Its field equations are commonly taught in graduate physics courses.

Relativity in practice
- Nuclear power plants can be made impossible without the ability to transform matter into energy.
- Our GPS system has to take into account the subtle effects of general relativity and special relativity, and if they don't, we will give inaccurate results.
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