Many NPCs you can chat to in order to get food, quests and information from.
To do this walk up to an NPC, make sure you are looking at them directly and literally just type into chat.
The NPC will reply to you, only people within 5 blocks will be able to overhear your conversation.
When the NPC chats to you some text will be in red, these are key words that can be spoken to the NPC in order to earn more about that subject, and to expand the conversation. Some words are not listed but if you ask the question you will get an answer.
If you are not sure where to start chatting then just type “help” this will start off your conversation with the NPC and give you some suggested words to say to get talking.
If an NPC has a note above their head then this NPC also has quests available, you can right click the NPC to view the quests available.