In programming, a library refers to existing code solutions to simplify web developers' tasks. Using the library routine function, the public library maintains a collection of pre-written useful resources. A programming language is a collection of files in which a particular program is formulated and can be quoted from other programs.

As is widely known, a "Library" traditionally refers to a building with a collection of materials, books, as well as media, and bookshelves. The library has shelves of books neatly organized so that we can use them whenever needed. Similarly, Programming library is a collection of useful programs that provides software development as books are collected and arranged in an easy to retrieve form so that they can be accessed.

In programming, this function is a component of the cited program.

For example, if you add fonts, the library can use it even from Excel and other applications. VISA library is a widely used software in measuring instruments.

In C language, the C standard library (header file), such as "#includ <stdio.h>" is used for programming. The programming libraries range from simple libraries with a single function to complex libraries with multiple functions.