This is often used by players in populated areas like World 1 Varrock West Bank where a trade offer quickly disappears in the volume of other public chat messages, or it's used to advertise a real world trading site.
Typically, they are used to perform tasks deemed overly tedious by real players, such as training a particular skill, collecting a certain item, or quickly typing an offer or phrase. Macros can be programmed to perform almost any task. Moreover, Jagex has the authority and power to reset or rollback a player's skill levels as well as his or her bank value before initiating a ban. Usage of macros is not allowed under the RuneScape rules (Rule 7) and may result in action taken against that player's account, such as a temporary or permanent ban.
The terms macroer, autoer, botter or bot usually refer to players who use such programs. A simple macro may just move the cursor to a certain position and perform a click while more advanced ones may interact with the game client directly. A macro operates by automating user input to the game. Macroing, botting, or autoing is the act of using third-party software to perform automated tasks. For the option under the chat interface, see Autochat.
