Operators determine the basis of how strong a programming language. The operators are a powerful tool which lets us perform many operations. The operators are the one which act on the operands to give the answer. 

There are three types of operators in C based on the number of operands it is acting on.

1. Unary operators (act on single operand)
2. Binary operators (act on two operands)
3. Ternary operators (act on three operands)

Say for example, we want to calculate 2+3*4, the answer is 14. We apply multiplication first over addition, due to BODMOS rule of mathematics. Similarly in C we have 15 different types of operators. To know which operator to apply first we have precedence chart for the operators. 

If we have expression like 2+3-4, we can see from precedence chart that both + and – have same precedence of 4. Which to apply first is addition or subtraction. This is decided by associativity. Whenever we have two or more operators with same precedence, we resolve it with associativity. 

Associativity Left to Right means, evaluate first what is coming in the left of given expression and Right to Left is vice-versa. (More about it we will see in expression evaluation).