The larger map can be opened by clicking "M" at any time or clicking the "M" next to the small map.
This map shows structures and NPCs, to the right there is a description of the area, and at the bottom there is a search bar.
You can add notes to your map by clicking the "Create Map Note" button in the lower right corner. This is made a small colored tag where you click.
You can also go to a location by clicking it on the map, you will automatically begin to run to this area.
Searching for mobs and NPCs is super easy with this map. Simply begin typing in the name of who your are looking for, spelled correctly, and a box with possible choices will pop out. Click the one you are searching for and it will show a blinking dot representing where that object is.
The smaller map is used for seeing things that are already close to your character.
From top to bottom, it shows what Nation and Channel you are in. There is an interactive dice game that you may play with people that are in close proximity with you, a button "M" to open the larger map, "W" to click the world map, and mail button. You may zoom out or in on the map at the bottom. In between the zoom buttons shows your coordinates and the three bottom buttons make this map small, medium, or large.
This is useful for seeing enemy people and mobs approaching you.