Messaging

In Dark Souls you can leave messages that appear in other players worlds to read and rate. The purpose of this is to help or hinder other players with tips about incoming traps and ambushes or hidden items, or to trick players with poor directions or promises of secrets that actually lead to death such as the infamous 'Try jumping' message. Messages can be nonsensical or humorous as well such as the message 'I can't take this...' or can be used to allow players to share in your joy or misery such as the message 'Praise the sun!'.

Dark Souls
You can leave a message in Dark Souls after you talk to Solaire of Astora. He will give you the Orange Soapstone which you can them use to leave messages. You can only leave a total of (insert # here) at any given time. Messages can also be rated by opening the message and pressing the back/select button. Rating a message gives the player who wrote the message one liquid Humanity. The player receives this humanity even if the message is down rated(someone plz confirm).

Dark Souls 2
Leaving a message is different from Dark Souls in that you no longer use an item and instead leaves messages by pressing start and selecting message from the menu. You can now leave significantly more messages than before and it is now more obvious how to rate messages but only possible to rate messages positively. Rating messages also has a different effect: you are healed when someone rates your message(other effects as well? plz add to page when discovered).