Entry point

In computer programming, an entry point is where the firsts instructions of a program are executed, and where the program has access to command line arguments.

To start a program's execution, the loader or operating system passes control to its entry point(During booting, the operating system itself is the program).

This marks the transition from load time(and dynamic link time, if present) to run time.

For some operating systems and programming languages, the entry point is in a runtime library, a set of support functions for the language. The library code initializes the program and then passes control to the program proper. In other cases, the program may initialize the runtime library itself.

In simple systems. execution begins at the first statement, which is common in interpreted languages, simple executable formats, and boot loaders. In other cases, the entry point is at some other known memory address which can be an absolute address or relative address(offset).

Alternatively, execution of a program can begin at a named point, either with a convertional name defined by the programming language or operating system or at a caller-specified name. In many C-famaily languages, this is a function named "main();" as a result, In JVM languages such as java the entry point is a static method named "main();" in CLI languages such as C# the entry point is a static method named "Main"