Across the top of the game interface is a single, box-like area that displays the current state of the character you are connected with. This is called the "Character Box" and it will keep you up to date about your character.
The first thing you'll notice is that it is split into three sections. We'll deal with each one individually.
This part of the character box displays who you are, what your character class is, how long you've been alive, and how many other players are connected to the game.
The circular icon to the left is your Character Class Icon. Different character classes have different symbols. In this case, the character connected is a Seraph - a type of Angel.
Next to that is the character's name (in this case, "Archon"). This is a hot link, and clicking on it will bring you to the character's profile page, where you can buy skills or perform other tasks.
Below that lie two bits of information: how many days has this character gone without being killed (19, in this case), and how many characters are currently logged into the game.
This part of the character box tells you a bit more meat about the character: his level, who he fights for, and so forth.
The top line displays the character's class and level. The next line says how many total Experience Points he has accumulated as well as how many he needs to gain a level (in this case, it is -1, which means the character has reached the maximum level).
Below that we are shown the character's faction membership (if any). This is a hot link to the faction profile page. In this case, Archon is a member of the Divine Army.
Below that we are shown his cult membership. Archon is a Squire (rank 1) in the Cult of Namm (one of the Elder Powers of Good). (Cult membership is an advanced element in the game, and is not available until you reach level 20 and choose a third-tier Character Class.)
This section shows you the vital statistics of your character: the meaty numbers.
You may notice that these numbers will automatically update while you are interacting with the map interface. This is intentional! It is showing you that something is happening without you being forced to reload the page.
From left to right, the numbers show your current Hit Points, Magic Points, Morality Score, Action Points, Character Points, and Cult Favor. Note that Cult Favor doesn't come into play until you reach level 20.