- 01Setting up (what you'll need)
- 02Your first shell script (echo)
- 03Using variables
- 04Command-line arguments ($1, $2 ...)
- 05Branching (the if statement)
- 06Repeating (the for loop)
- 07Repeating (the while loop)
- 08Writing your own function
- 09Working with arrays
- 10Command substitution ($())
- 11Working with strings (parameter expansion)
- 12Reading from standard input (read)
- 13Exit status and && / ||
- 14Pipes and redirection
- 15The case statement
- 16Arithmetic ($(( )))
- 17The basics of grep, sed and awk
- 18Argument checks and error handling
- 19Function return values and exit codes
- 20[Project] Build a small log-tallying script
Using variables
This lesson covers the basics of variables in a shell script.
A variable is declared as name=value. The rule peculiar to shell scripting is that there must be no space on either side of the =. To use the variable you write $name.
The sample code declares two variables, name="Alice" and age=14, and embeds them in a string to print.
A common early stumble is adding spaces, as in name = "Alice". With spaces around the =, the shell reads the line as running a command instead, and it fails.
In professional work, collecting file paths and configuration values into variables is what makes a script easy to reuse and to change.
๐งช This site can't compile or run Shell Script directly, so it checks on the spot whether what you typed matches the reference code (scoring happens entirely in your browser โ nothing is sent anywhere).