Videos
Linux & the command line
Pick a topic to watch.
14 video lessons
2:00
Lesson 1
The shell and the prompt
When the terminal is ready it shows a prompt and waits. Most people look straight past it, and it is already telling you three things. The first word is who…
2:08
Lesson 2
Moving around
Folders — Linux calls them directories — hold files and other folders, and the whole lot is one tree. A single slash at the top is the root, and there is…
1:56
Lesson 3
Reading files
The simplest way to read a file is c a t, which prints the whole thing straight to the screen. Four lines in the file, four lines of output. The odd name is…
2:32
Lesson 4
Creating and removing
Two commands make things. M k d i r makes a directory — a folder. Touch makes a file. And note what kind of file: touch makes it empty, zero bytes, but it…
2:05
Lesson 5
Wildcards
A wildcard is a symbol that stands for "anything", and it turns one command into a command about many files. Star dot t x t means every name ending in .txt…
1:54
Lesson 6
Saving output to files
Normally a command's output appears on screen. Add an arrow and a filename and it does not — and the first time, that looks like nothing happened. It did: the…
2:01
Lesson 7
Pipes — joining commands
This is the idea the command line is built on. A pipe sends one command's output straight into sort, as its input. Cat produces five lines; sort receives those…
1:58
Lesson 8
Searching with grep
Grep searches for a word and prints only the lines that contain it. Give it error and this log file, and out of five lines, one comes back. On a file this…
1:59
Lesson 9
Finding files with find
You have known l s since lesson two, and it has one limit: it shows only what is right here, in this one folder. Find does not stop there. It walks every…
2:20
Lesson 10
Sorting and columns
Sort arranges lines in alphabetical order. Three fruits go in unordered and come back apple, fig, pear. Dash r turns it round and gives you the reverse. Sort…
2:20
Lesson 11
File permissions
Run l s dash l and every line starts with ten characters that look like line noise. They are not. They are four fields: one, then three threes. The first…
2:00
Lesson 12
Users and sudo
Linux was built from the start for many people to share one machine safely. Each person gets an account, and your files are yours: you cannot read or change…
2:04
Lesson 13
Programs and processes
Two words that sound the same and are not. A program is a file sitting on disk, doing nothing. A process is that file running — your browser, your editor, and…
2:27
Lesson 14
Software, settings, next steps
On Linux you almost never download an installer. A package manager fetches software for you, from a checked source. The same idea has different names on…