What's better. Minecraft or Terraria?

They are both good in there own ways but if you were playing without mods I would choose Terraria since it has more to it then Minecraft does.

I personally like Minecraft better. The gameplay is more complex and entertaining than Terraria.

Minecraft is more open worldly than terraria. You can roam, do whatever you want. Go to different dimensions. Fight bosses (there's only 2 (some could argue 3) though) Its fun and can be very interactive in it's play style with how you mine for resources, build your house, explore, use the land to your advantage.

Terraria is less open worldly than minecraft. The world has it's limits. However let me tell you that if you choose the large world, you can put on some fast freakin' boots and still take a couple minutes to run from edge to edge. It has MUCH more variety than minecraft, with many more ores, enemies, tools, weapons, weapon types (i.e. Swords and bows and spears and yoyo's (yep. And many more bosses. Like 15 or so depending on your platform. It can be just as interactive in it's environment with mining and exploring (although minecraft beats it out for world exploration) It is a bit more difficult to play with friends I think. Seeing as minecraft has MANY public servers people run (and given I haven't looked into public terraria servers, but it seems like with the playstyle of terraria, a public server would be odd.)

To sum up, Minecraft is better for world exploration and playing with friends. Terraria is better if you want a ton of variety and a bit more challenge in boss fights (it also has quite the learning curve but as you play and look at the wiki, it gets easier)