DAX function

AND && — DAX function reference

All conditions true.

Syntax

dax

AND(<logical1>, <logical2>)    <logical1> && <logical2>

dax

[Active] && [Approved]

→ true / false

dax

AND(Sales[Amount] > 0, Sales[Quantity] > 0)

→ true / false

&& chains any number of conditions; nesting AND() calls to do the same is much more verbose.

dax

Sales[Amount] > 0 && Sales[Region] = "West" && NOT(ISBLANK(Sales[CustomerID]))

→ true / false

AND() takes only two arguments; the && operator chains more cleanly.
AND() is strictly binary — combining three or more conditions requires nesting AND(AND(a,b),c) or, far more commonly, just using && which chains naturally.
Both operands are always evaluated; DAX does not guarantee short-circuit evaluation the way some languages do, so don't rely on the second condition being skipped when the first is false.

From Logical & error handling