A dummy is a sandbag that players can train on. It only gives 5 Attack experience per hit, but it does not deal any damage, so it is ideal for players just starting out. Dummies are in Varrock in the building north of Varrock's East Bank.
Low-level players can train on them until they reach an Attack level of 8. After this, if they attempt to hit the dummy again, they won't be allowed to hit it and will receive the message, "There is nothing more you can learn from hitting a dummy."