① Arithmetic calculator-can perform simple four arithmetic operations such as addition, subtraction, multiplication, and division, also known as simple calculator. They are generally physical calculators.

②Scientific calculator-can perform operations such as power, square root, exponent, logarithm, trigonometric function, statistics, etc. It is also called a function calculator. It can be software or physical objects.

③Programmer’s calculator-a calculator specially designed for programmers. The main feature is that it supports And, Or, Not, Xor: the most basic AND NOR and XOR operations, shift operations Lsh, Rsh: the full name is Left Shift And Right Shift, that is, left and right shift operations.

④ Statistical calculator-a calculator designed for people with statistical requirements. It can be software or physical objects.