1. Operating system
2. Unix operating system and its basics
3. Unix architecture
4. Difference between Linux and Unix
5. System call
6. Kernel
7. Shell and its types
8. Unix commands and shell programming
9. Internal and external command
10. Files in Unix, inode
11. Path, Absolute path, Relative path
12. File Ownership, access method & permissions
13. Wild card characters
14. File descriptor
15. Pipelining
16. Process
17. Shell Scripting