What do you do when Minecraft says out of memory?

There are some options you can consider.

# Clear up memory by closing running applications. (this can be done also by restarting the computer and not starting new applications)

# Buy more memory : you should be careful which memory type you buy because it must be compatible with your system. (If you have enough money and your computer is kinda outdated you can also consider buying a new one with more and faster memory.)