A player can play alone or they can make their game public so others (who they may not know personally) can join. They can also invite their friends to join them in a game. Players can send messages and use voice chat with other players. On some Diablo games, players can spend money to buy and sell items.
Parents can set parental controls using the Blizzard Games Parental Portal. This allows parents to do things like disable in-game purchases and set time limits for play. There are additional safety settings available through the game’s settings menu such as the ability to block and report other players, and on the gaming platforms being used to play the game on e.g. PlayStation.