Day1.
Unit 1. 기본 shell concepts
Unit 2. variables 
Unit 3. return codes and traps

Day2.
Unit 4. Flow control
Unit 5. shell commands

Day3.
Unit 6. arithmetic
Unit 7. shell types， commands， functions

Day4.
Unit 8. 그외 shell 변수들.
Unit 9. regular expression & Text selection

Day5.
Unit 10. sed utility
Unit 11. awk program
Unit 12. Good practices and review