OPERATING SYSTEM
by Illeana Urn

1. HARDWARES
1.1. cpu
1.2. main memory
1.3. input devices
1.4. output devices
2. USER
3. COMPONENTS OF OS
3.1. KERNEL
3.2. SYSTEM PROGRAMS
3.3. USER INTERFACE
4. CHARACTERISTICS
4.1. SYSTEM CALLS
4.2. CONTEXT SWITCHING
4.3. PERFORMANCE
4.4. CONCURRENCY
5. SOFTWARES
6. PROCESS MODES OF OS
6.1. USER MODE
6.2. KERNEL MODE
6.2.1. INTERRUPTS
6.2.2. TRAPS
6.2.3. SYSTEM CALLS