What is it?

• A family of operating systems (SunOS, Solaris, BSD)
  
  

• Kernel
  • Controls hardware, memory allocation, etc.
  • User doesn't directly interact with it
• Shell
  • Where you type your commands
  • Protects you from the kernel (and vice versa!)
  • Some common shells:
    • sh - Bourne shell
    • csh - C shell (no pun intended!)
    • bash - Bourne again shell
    • tcsh - extension of C shell
• Tools/Applications
  • Email, word processing, etc.

History:

• Developed at AT&T Bell Labs in 1960s
• Was for "family and friends"
• Sold to universities for CHEAP!
• Users started adding on
• Became commercialized in last 10-15 years

Why do people use it?

• Designed for numerous users to share resources
• Multitasking
• Building blocks (can be added or removed easily)
• Functionality not hidden behind menus
• Let's user have more control, power
• More secure(?)