Variables

A variable stores a value — text, a number, or any object — so you can use it later. Variable names start with $.

$city = 'Lagos'
$temperature = 24
"It is $temperature degrees in $city"

$temperature = 27
$temperature += 1
$temperature

It is 24 degrees in Lagos
28

• Assign with = (spaces around it are fine).
• +=, -=, *=, /= update a variable in place; $count++ adds one.
• Variable names aren't case-sensitive: $City and $city are the same.

Variables can hold objects — and whole results

$numbers = 1..10
$evens = $numbers | Where-Object { $_ % 2 -eq 0 }
$evens.Count
$evens -join ', '

5
2, 4, 6, 8, 10

Storing a command's output in a variable lets you reuse it without running the command again.

Automatic variables

PowerShell sets some variables for you:

Common mistakes

• Forgetting the $: city = 'Lagos' tries to run a command called city.
• Using a variable before assigning it — it's $null, so things quietly go wrong. Set-StrictMode -Version Latest (Level 3) turns that into an error.

Practice

Store a product name and a price in variables and print Coffee costs 3.5.

$product = 'Coffee'
$price = 3.5
"$product costs $price"

Coffee costs 3.5