First day with the terminal

This is a short orientation for someone opening a terminal for the first time. Each OS uses a different shell, so the same task uses slightly different commands. There is no need to memorize them — keep the table nearby and they settle into muscle memory through use.

1. Distinguishing terminal, shell, and console

• Console — the device or its abstraction that displays input and output.
• Terminal emulator — a graphical program that mimics a console as a window. macOS Terminal.app, iTerm2, Windows Terminal, GNOME Terminal.
• Shell — the interpreter that takes typed commands and hands them to the OS. bash, zsh, PowerShell, cmd.

A shell runs inside a terminal emulator. Most people just call the whole thing "the terminal."

2. Where to open it

OS	Terminal
macOS	Cmd+Space → "Terminal" or "iTerm"
Windows	Start menu → "Windows Terminal" or "PowerShell" or "cmd"
Linux (GNOME)	Ctrl+Alt+T or Activities → Terminal

Windows Terminal is a host app that displays PowerShell, cmd, and WSL together as tabs. Bundled by default with Windows 11.

3. Checking position and moving

Shell	Command	Sample result
bash/zsh	pwd	/Users/alice/projects
PowerShell	pwd (or Get-Location)	C:\Users\alice\projects
cmd	cd (no arg)	C:\Users\alice\projects

Action	bash/zsh	PowerShell	cmd
Into a sub-folder	cd src	cd src	cd src
Up a folder	cd ..	cd ..	cd ..
Home directory	cd ~ or cd	cd ~ or cd $HOME	cd %USERPROFILE%
Absolute path	cd /etc	cd C:\Windows	cd C:\Windows
Switch drive	(n/a)	cd D:\	D: then cd \work

In bash, cd - returns to the previous directory. PowerShell 7+ behaves the same.

4. Listing, clearing, viewing files

Shell	Default	Include hidden	Detailed
bash/zsh	ls	ls -a	ls -la
PowerShell	ls	ls -Force	ls | Format-List
cmd	dir	dir /a	dir /a /q

PowerShell's ls is an alias; the real cmdlet is Get-ChildItem. cmd has no ls.

Clearing the screen — clear (bash/zsh), cls (PowerShell, cmd), Ctrl+L (most).

Viewing file contents — cat file.txt (bash), Get-Content file.txt (PowerShell), type file.txt (cmd). For larger files use less (Unix) or more (Windows) to page.

5. Exiting and common keys

To exit — exit. Or:

• bash, zsh, PowerShell — Ctrl+D (with empty input).
• cmd — Ctrl+Z then Enter (rarely works).

Useful keys:

Action	Key
Autocomplete	Tab (single press: one candidate / double press: list candidates)
Previous command	↑
Next command	↓
Interrupt command	Ctrl+C
End of input (EOF)	Ctrl+D (Unix · PowerShell) / Ctrl+Z then Enter (cmd)
Beginning of line	Ctrl+A
End of line	Ctrl+E
Reverse search	Ctrl+R (bash, zsh, PowerShell PSReadLine)

Ctrl+C sends SIGINT (interrupt) to the running process. When an interactive program (Python REPL, node, top) refuses to budge, this is the first key to try.

6. Side-by-side comparison

# bash · zsh
pwd
cd ~/projects
ls -la
cat README.md

# PowerShell
pwd
cd ~\projects
ls -Force
Get-Content README.md

:: cmd
cd
cd %USERPROFILE%\projects
dir /a
type README.md

7. A small practice flow

1. Move to home directory — cd ~ (cmd: cd %USERPROFILE%).
2. Make an empty folder — mkdir hello && cd hello.
3. Make an empty file:
   • bash · zsh — touch a.txt.
   • PowerShell — New-Item a.txt -ItemType File.
   • cmd — type nul > a.txt.
4. Check the listing — ls or dir.
5. Step back up — cd ...
6. Remove the folder:
   • bash · zsh — rm -rf hello.
   • PowerShell — Remove-Item hello -Recurse -Force.
   • cmd — rmdir /s /q hello.

rm -rf and Remove-Item -Recurse -Force delete permanently and immediately. They do not pass through the recycle bin. The first few days, double-checking the path is a safe habit.

8. Common pitfalls

A path with spaces — cd My Documents parses as two arguments and fails. Wrap in quotes: cd "My Documents".

Hidden files invisible — Finder on macOS hides them by default. ls -a (Unix) or ls -Force (PowerShell) is needed.

cd not crossing drives — in cmd and PowerShell 5.1, typing only a drive letter like D: jumps to that drive's last visited location.

Autocomplete misbehaving — a Korean IME can swallow some keys. Try in English mode.

Looking up a command — Unix man <cmd>, PowerShell Get-Help <cmdlet> or <cmdlet> -?, cmd <cmd> /?.

Closing thoughts

The terminal feels foreign at first, but once five commands (pwd, cd, ls, cat, mkdir) settle into your hands it becomes routine. Three keys give the largest efficiency boost: Tab autocomplete, ↑ previous command, Ctrl+C to interrupt. For irreversible commands like rm -rf, double-check the path during the first few days.

Next

• data-formats
• wsl2

The Missing Semester Shell Tools · Microsoft Windows Terminal · GNU Coreutils · PowerShell about_Command_Syntax · SS64 shell reference for reference.