Take English as an example. There are only 26 alphabets, and using those 26 alphabets you make words to communicate with other people. But in Chinese there are countless numbers of words (and it's NOT alphabets). They're different characters with different meanings, and you use those characters to make up words/sentences/etc.
In English there are idioms, but Chinese idioms are usually made up of 4 characters.
There are different characters for different levels... Start with the easy ones if you're a beginner.
