JavaScript

let vs const in JavaScript

JavaScriptVariableslet vs const reassignmentbeginner

What this snippet does

let allows reassignment; const binds the variable permanently to its initial value.

Expected output

20
100

Why practise typing this

Typing variables code builds muscle memory for the symbols and indentation JavaScript uses most, which prose-based typing tests never cover. DevType measures your words per minute and accuracy on this snippet and tracks the individual characters you mistype, so later lessons can target them.

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