Hi, well
If you win games, you'll gain points. Other way round, if you lose games, you'll drop points.
According to the opponent's strong, you'll win or lose more or less points.
For Example, If your opponent is stronger than you and you win the game, your points will increase more compared to if you win against an opponent with less points than you.
I don't know if I explained well, Sorry for my english 
And of course the whole goal of the rating system is simply to make it easier to find an opponent of similar strength.
Hi! My name is Lauren Goodkind and I’m a chess coach and chess YouTuber based in California:
https://www.youtube.com/channel/UCP5SPSG_sWSYPjqJYMNwL_Q
And if you have a draw, you might loose or win points, depending on who you play with. Or your rating might stay the same.
For example: If your rating is 500 and drew against a 1500 rated player, then you would gain points.
If you drew another 500 rated player, then your rating would stay the same.
If you drew a 100 rated player, then you would lose points.
I hope that this helps.
The rating difference between players is a statistical measure for the scoring probability. If you are 100 points stronger than your opponent, you should score roughly 65%. 200 pts: 75%, 300 pts: 85%, 400 pts: 90%, 500 pts: 95%.
Hi, well
If you win games, you'll gain points. Other way round, if you lose games, you'll drop points.
According to the opponent's strong, you'll win or lose more or less points.
For Example, If your opponent is stronger than you and you win the game, your points will increase more compared to if you win against an opponent with less points than you.
I don't know if I explained well, Sorry for my english
It indicates how good you are at chess to match you with opponents of similar strength. (Can also be used as bragging rights)
So, your rating is a number that tells how good you are at chess.
The higher your rating is, the better you're at chess.
It improves by going up, so let's say you're a 500 rated player.
You win and you'll add points. You add more or less points based on what rating your opponent is. If you won against a 400 rated player, your rating won't go up as much if you won a 1200 rated player.
If you lose, your rating will decrease, or it will stay the same. Let's say you lose to someone who is lower rated than you. You'll lose more points. If you lose to a 1500 rated player, your rating is most likely not going to decrease, and instead it'll probably stay the same because your opponent's rating is way to high for you.
Draw is like what @laurengoodkindchess said: https://www.chess.com/forum/view/for-beginners/rating-what-does-it-mean#comment-61553839
Hope this helps.
Also, the rating system can be misleading. On chess.com, for instance, you are playing people from all over the world, so with a rating of 1200 you can be pretty sure you're about equal with other 1200 players. On the other hand, my local chess club has a vast majority of players that are rated much higher than I am. So in order to increase my OTB (over the board) rating, I have to beat them on a fairly regular basis. Therefore, even if my performance ability increases by 50 to 100 points, my numerical rating isn't going to move much. It's like pitting yourself against Dwayne Johnson in arm-wrestling. At first you lose every match. Then you dedicate yourself to two years of training and proper diet, etc., and you are much stronger than you were before. And then you arm-wrestle Dwayne Johnson again. And you lose every match. So your progress against Dwayne Johnson isn't really a measure of your progress at all.
As statistics go there are some glitches. At my level say 1600 blitz. If I played the world champion say 3200. I would play 100 games. Odds are he will win all 100 or very very very close. My score would go down to a level well below my ability. Its basically an excellent system. You match up against your playing ability and win half of the time. As you improve your score goes up.
Somewhere online I read about how they came up with the FIDE scoring system. I thought it was an interesting read. But I like statistics so that helps.
As statistics go there are some glitches. At my level say 1600 blitz. If I played the world champion say 3200. I would play 100 games. Odds are he will win all 100 or very very very close. My score would go down to a level well below my ability. Its basically an excellent system. You match up against your playing ability and win half of the time. As you improve your score goes up.
Somewhere online I read about how they came up with the FIDE scoring system. I thought it was an interesting read. But I like statistics so that helps.
If you are 1600 and lose to a 3200 100 times, your rating loss will be exactly 0.
Thanks! I had the same question!
As statistics go there are some glitches. At my level say 1600 blitz. If I played the world champion say 3200. I would play 100 games. Odds are he will win all 100 or very very very close. My score would go down to a level well below my ability. Its basically an excellent system. You match up against your playing ability and win half of the time. As you improve your score goes up.
Somewhere online I read about how they came up with the FIDE scoring system. I thought it was an interesting read. But I like statistics so that helps.
Losing against someone 1000 points higher than you won't lose you rating points. So you can basically play with the world champion all you want whether it be rated or unrated without worrying about losing any of your points if your like a 2500 rated player or less.
What the rating system mean?
How does it improve/fail