Linux OS
Linux is a free(dom) UNIX-type operating system.
Linux gives an increased functionality & more stability ,crashes caused by software are rare. Linux comes standard with a benchmark C/C++ compiler and built-in support for many other languages, including Java.The softwares which are available now for linux & would have cost thousands of dollars extra.
The most popular linux flavor now is Ubuntu
Rapidly incresing Linux grassroots and corporate popularity like Firefox
- Linux establishing itself in the public consciousness as a good desktop OS; expect traditional and viral marketing (2008)
- OEM preloads of Linux, especially Ubuntu, rapidly increasing.
Linux file system is like a Unix file system, Its is based on one root directory, or hierarchical top point with subdirectories underneath. Some sub-directories act as mount points, Ther different physical or networked file systems may be incorporated.
The hardware is also incorporated into the file hierarchy.
Device drivers interface to user applications via an entry in the /dev directory. Process information as well is mapped to the file system through the /proc directory.
Unix security systems were designed into the architecture. Raw hardware devices are protected from direct access, and the file system has an inbuilt security system giving individual access to files on three levels, user only, group membership, and world access. Each category has read, executable and write flags.
Linux Kernel
The Linux kernel includes
multitasking
virtual memory
shared libraries
demand loading
shared copy-on-write executables
proper memory management
TCP/IP networking.
Linux is a module-loading monolithic kernel. Device drivers and kernel extensions typically run in ring 0, with full access to the hardware, although some run in user space.
Device drivers are easily configured as modules, and loaded or unloaded while running the system.