• Argument Passing with Parsing
• User memory Access
• System call Handler
• System call Implementation(exec(), exit(), write(), read())

• Base File system
• File system call Implementation(create, remove, open, close, filesize, read, write, seek, tell)

• Scheduler
• Alarm Clock
• Aging & BSD Scheduler
• Threads
• Synchronization

• Page Fault Handler
• Page Table
• Stack Growth