Does buying minecraft with a card in stores make it accessible from other computers?

I'm planning on buying Minecraft with a game card sold in stores. However, I was wondering if buying it from a store will make it accessible from other computers.

Yeah its fine, its like Warcraft 3- i have a Warcraft 3 battle box but even though i changed computers it adds it to your account not your computer

You can access your account from other computers, but not your worlds. You'll have to transfer save data with a USB stick.