---
title: "Terminal & Shell"
space: "Teacher's Handbook"
url: "https://portal.cs17.org/teachers-handbook/q2/terminal"
updated: "2026-09-24"
---

The idea at this point is to make them **comfortable** with working in the terminal. When programming foundations start, it will pay off.



Base material:

![CS17_Terminal_Shell_Lesson_Plan_No_Programming.pdf](/files/CS17_Terminal_Shell_Lesson_Plan_No_Programming.pdf)



### Session 1

- File System
  - Draw on board the tree (root > folder > more folders etc.)
  - They have been creating this through UI (mouse till now)
- Terminal vs Shell
- Commands:
  - `pwd`
  - `ls`
  - `cd`
    - explain:
      - `cd ..`  and `cd ~`  (\~ is home, **not** root)
  - `mkdir`
    - when they try to make multiple directories using one command each, show them `mkdir d1 d2 d3` (faster than UI, they can start to see the value!)
    - Also, what if "d1 d2" should be file name, need to **wrap in quotes**.
  - `touch`
  - `cat`
  - `echo` 
    - Then combine echo with `>`:
      - `echo "Hello World" > file.txt` 
      - `>>` for append
  - `cp`
  - `mv` : show both move and rename with this
  - `rm`
  - `rmdir`



Practice in between, ask them to create this structure using terminal commands they just learned:

```plaintext
Frappeverse
-------> photos
--------------> mumbai
----------------------> all.txt
-------> blog
-------------> <your-name>.txt
```

### Session 2  &lt;Practice with TAs&gt;



Make them run commands on their computers (by Shivam)



### Session 3

- `history`
- `Tab` Completions and Up Arrow Key for navigating through history
- `grep`  (the very basics) (take an example where the file contains multiple lines and occurrences of the word)

```
grep apple fruits.txt
```

- Command anatomy:
  - e.g. `cp hello.txt backup/` 
  - `command argument argument`
- Flags
  - e.g. `ls -l` `ls -a` (good time to make them see the difference that just `ls` will not show hidden (i.e. starting with a `.`) files and folders.
- `wc` (stands for **word count**):

```bash
wc fruits.txt # 5 14 65 story.txt
wc -l fruits.txt # 5 story.txt
```



In the above, 5 is the number of lines, 14 is the number words, and 65 is the number of bytes in the given file(s). If `-l` option is given, only number of lines are printed.



- `man` (manual pages) and `--help` 
  - show for `wc` etc. 
  - they should be able to at least skim
- Wildcards
  - e.g. list all `jpg` images in a file, all files starting with the letter `p`
    - `ls *.jpg` and  `ls p*`
  - then expand to show how the wildcards are not just in `ls` but can be used to carry out copy, move etc. 
    - move all `jpg` images to `images/` folder etc.
    - e.g. `math_1.txt math_2.txt math_3.txt cs_1.txt cs_2.txt cs_3.txt` move math notes to `math/` folder and cs notes to `cs/` folder.

### Session 4 &lt;Practice with TAs&gt;

Practice with TAs.

### Session 5

- `head` and `tail`
  - head / tail by default 10 lines
  - `head -n 5` first 5 lines, with tail last 5 lines.
  - show examples
- (important to understand) redirection
  - analogy of redirecting someone from where he was actually "directed" towards
  - **it was going to come *on screen*, but we asked the shell program to *redirect it to some file* instead**
  - Show if "ls &gt;&gt; list.txt",  list.txt will get auto created if not exists, don't have to touch.
- (important to understand) pipe
  - Again analogy to actual pipe connecting different chambers (e.g. water treatment plan) where each chamber does some mixing and the contents are forwarded to the next output pipe
  - Take examples and make them practice:

```bash
$ ls | grep "apple" # list of files/dir that have apple in their name
$ history | tail -n 50 | grep "mkdir" > commands.txt
```



Good opportunity to give textual questions and **see if they can breakdown the problem** and chain the commands to get it done.