Does a land count as being played if you put it onto the battlefield with a spell?

"Playing a land" is a defined game action under CR 305.1: you play a land from your hand during your main phase when the stack is empty, and it counts against your land play limit for the turn.

When a spell or ability puts a land onto the battlefield (e.g., Cultivate, Primeval Titan's trigger), that is a separate effect governed by the spell/ability's instructions. It does not use the "play a land" action and therefore does not count against your one-land-per-turn limit.

This means effects like Explore or Fastbond that care about "playing" a land will not trigger or apply when a land enters the battlefield via a spell or ability — and vice versa, putting a land onto the battlefield this way won't be stopped by effects that restrict how many lands you can "play."