FTA:

The big news this month is that “conveyor belts have unlocked the Y axis” in Terraria 1.4.5, meaning that you can now send items up and down along with using them to transport goods horizontally. Not only will that make them a lot easier to use generally, making it easier to navigate across long distances, but the demonstration also shows them hooked up to a chest, allowing you to instantly store all your transported items. That’s a massive convenience improvement, and will almost certainly lead to some fascinating new creations.