# System calls

This chapter describes the `system call` concept in the linux kernel.

* [Introduction to system call concept](http://0xax.gitbooks.io/linux-insides/content/SysCall/syscall-1.html) - this part is introduction to the `system call` concept in the Linux kernel.
* [How the Linux kernel handles a system call](http://0xax.gitbooks.io/linux-insides/content/SysCall/syscall-2.html) - this part describes how the Linux kernel handles a system call from an userspace application.
* [vsyscall and vDSO](http://0xax.gitbooks.io/linux-insides/content/SysCall/syscall-2.html) - third part describes `vsyscall` and `vDSO` concepts.
* [How the Linux kernel runs a program](http://0xax.gitbooks.io/linux-insides/content/SysCall/syscall-3.html) - this part describes startup process of a program.