LINUX Device

In Linux, devices can usually classified as the below three typies:

• Block device
• Character device
• Network device

Block device: accessed by block.  It supports the random access to the device. Usually can be accessed as the file system.

For example: hard disk. SSD.  CDROM,

Character device: accessed by sequence.  Character by character or byte by byte.  For example, keyboard, mouse, printer and pesdo terminals.

Network devices: Ethernet adapter. Accessed by socket.

There are some other devices in the system but they are not actual any physical device. they are called pseudo devices

eg: /dev/random ,urandom, /dev/zero, /dev/null,  /dev/stdin, /dev/stdout, /dev/loop