Today, mathematics is used throughout the world in many fields, including natural science, engineering, medicine, and the social sciences such as economics. Applied mathematics, the application of mathematics to such fields, inspires and makes use of new mathematical discoveries and sometimes leads to the development of entirely new disciplines. Mathematicians also engage in pure mathematics, or mathematics for its own sake, without having any application in mind, although applications for what began as pure mathematics are often discovered later.

- 21 branches by math handbook
### Classification by domain

#### Real math

- JavaScript math for front end webpage
- Java math for back end server
#### Complex Math

- Complex math calculated by Function calculator

complex operation of special function should be converted to complex( ) by the tocomplex( ) before calculation. - Complex math calculated by Matrix calculator
- Complex math calculated by mathHandbook calculator

complex operation should be converted to complex( ) by the tocomplex( ) before plot.### Classification by variable

- numeric math calculated by funplot - JavaScript function calculators
- Ordinary Differential Equation (ODE) calculated numerically by ODEplot calculators
- symbolic math calculated by mathHandbook - math calculators

clicking individual button go to its calculator.

the Math Handbook Calculator has the function of machine learning. It is unique in the world to solve the function of any order (such as 0.5 order) differential equations. Enter mathematical formulas on the Mathematics Handbook website, click continuously to calculate calculus, solve equations, give analytical solutions and numerical solutions and diagrams, interactively zoom in the drawing, and zoom in with the mouse wheel. You can use it on your mobile phone to learn computing and development anytime, anywhere.

- html + JavaScript : DrHuang.com/index/html
- JavaScript or mathHandbook programmimg = math coding : DrHuang.com/index/mathHand
- python programimg : DrHuang.com/index/python

- complex - complex function - complex math
- math handbook chapter 10 complex function
- complex animate(z) for phase animation, the independent variable must be z.
- complex plot(z) for phase and/or modulus, the independent variable must be z.
- complex2D(x) for complex 2 curves of real and imag parts, the independent variable must be x.
- complex3D(x) for 3 dimensional graph, the independent variable must be x.
- color WebXR surface of complex function on complex plane
- Riemann surface - Complex Branches - complex coloring

- Math - Symbol - Handbook - math word
- Elementary Math - Higher Math
- Calculator - mathHand - mathHandbook
- Function - Formula - equation - graphics
- Fractional Calculus - differential equation
- Example :