applied mathematics
It is a general term for mathematical theories and methods with clear application purposes. Studying how to apply mathematical knowledge to other fields (especially science) can be said to be the opposite of pure mathematics, including differential equation, vector analysis, matrix, Fourier transform, complex variable analysis, numerical method, probability theory, mathematical statistics, operational research, cybernetics, combinatorial mathematics, information theory and many other branches of mathematics, as well as from various application fields.
"Basic Mathematics"
A major category of mathematics. It is based on the inherent needs of mathematics or possible future applications to study the inherent laws of the mathematical structure itself, and has no direct relationship with seeking the common ground of other disciplines to solve practical problems.
Basic mathematics, also called pure mathematics, specializes in the internal laws of mathematics itself. The knowledge of algebra, geometry, calculus and probability introduced in the textbooks of primary and secondary schools belongs to pure mathematics. A remarkable feature of pure mathematics is to temporarily put aside the specific content and study the quantitative relationship and spatial form of things in pure form.