Pendragon is a role-playing game set in a fictionalized time of Arthur Pendragon in Briton in the early 6th Century.  Players play the part of knights.  There are some important concepts in Pendragon that should guide your character's actions.

Chivalry

Chivalry is very important.  You do not have to be chivalrous.  However, the consequences for acting against the principles of chivalry can be harsh.
From the Song of Roland:

To fear God and maintain His Church
To serve the liege lord in valour and faith
To protect the weak and defenceless
To give succour to widows and orphans
To refrain from the wanton giving of offence
To live by honour and for glory
To despise pecuniary reward
To fight for the welfare of all
To obey those placed in authority
To guard the honour of fellow knights
To eschew unfairness, meanness and deceit
To keep faith
At all times to speak the truth
To persevere to the end in any enterprise begun
To respect the honour of women
Never to refuse a challenge from an equal
Never to turn the back upon a foe

Honor

Honor is also important.  If your Honor drops enough, you will lose your knighthood.  Be very careful about insulting other knights or Ladies.  Any insult can result in a duel, either to first blood or to death.  Knights take their honor VERY seriously.

Combat

Combat in Pendragon can be deadly, especially when faced with monsters that can do a lot of damage in one blow.  It will be rare that you will die if your side wins the battle but it can happen.  More serious is that there is very little healing in Pendragon.  While you might get a d6 or so from a successful healing skill roll, most of your healing will be at ~3 hp per week during total bedrest.  Meaning that if you lose half of your hp in a battle you might be lying on your back for the next 4-5 months.

Personality Traits define the basic manner in which your character behaves.  Periodically, you will have to roll against a Personality Trait to see what you do in a given situation.  Meet an attractive young maid at the feast?  You can roll against Chaste to see if you resist her charms or against Lustful to try to hook up.  Rolling under your score is a success.  Rolling your score exactly is a critical.  Rolling above your score is a failure.  Rolling 20 (unless your score is 20+) is a fumble.  If your score in something is above 20, you cannot fail and you add +1 to the die for each value above 20.  So a 25 gives you a plus 5 and 15 or better is a critical.

When you use a Personality Trait as part of the story, the GM may announce that you have gotten a "check" in that trait.  Put an "X" in place of the "_" next to that trait on your character sheet.  During the Winter Phase, you will roll against your checked traits to see if any of them increase.  In this manner, your Personality Traits will tend toward the way you play your character.  Always drinking too much at the feasts?  Your Indulgent will tend to rise.

Passions are things and people your character feels strongly about.  In certain circumstances you can roll against your passions to determine your attitude or actions.  In addition, in certain circumstances you can invoke a passion.  Doing so can have dramatic effects.   Defending you Lady Fair's honor in a duel against another knight?  You can invoke you Amor or Love for her and if successful you will earn pluses for the combat.  If you fail, you will earn minuses and could lose points in your Amor/Love.  It is generally unwise to invoke Passions that are not at least 15.

Statistics are the basic measurements of your character, how large (SIZ), how quick (DEX), how powerful (STR), how much endurance (CON), and how attractive (APP).  Other than SIZ, you can raise them using advancement points at the end of each year.  They affect how much damage you deal, how fast you heal, how fast you move, and how much damage you can take.

Skills are a measurement of your facility in various disciplines.  Skills can be grouped to some extent into Knightly skills (Combat skills, Heraldry, and Tourney), Social skills (Falconry, Gaming, Orate, and Hunting), Romance skills (Compose, Dancing, Flirting, Play, and Romance), Courtly skills (Courtesy, Heraldry, Intrigue, and Recognize), Survival skills (Awareness, Boating, Chirurgery, First Aid, and Swimming), and Knowledges (Faerie Lore, Folk Lore, Industry, Read, Religion, and Stewardship).

Knightly skills are important for gaining Glory as they are commonly used on quests and in tournaments.  Social skills are useful for impressing other knights.  Survival skills can make a real difference during adventures.  Knowledges, especially Stewardship, can help your character figure things out.

In the early period of Arthur's reign, Romance skills are useful for getting a woman's attention but are unlikely by themselves to lead to marriage as a Father's (or other man's) approval is almost always necessary.  Glory and Wealth are what make an attractive suitor.

There are two types of dice rolls, opposed and unopposed.

Opposed resolution occurs when you are competing with someone else.  Combat is an example of opposed resolution.  A second example is gaming, where the two contestants roll their gaming skill against one another.  Another example is trying to bed that serving wench at the feast, she rolls her Chaste versus your Lustful.

In opposed resolution, the highest success wins.  Knight A and Knight B are playing chess.  Knight A has a skill of 8 and rolls a 2 while Knight B has a skill of 4 and rolls a 3.  Knight B wins.  A critical is always considered the highest possible success and beats any non-critical.

In combat, the highest successful roll does damage to the opponent.  If both combatants are successful, the loser's shield blocks part of the damage.  If both succeed with the same number, neither does damage and any non-sword breaks.  A critical in combat does double damage.

Unopposed resolution is used when a character is attempting to succeed at something that does not involve competing with others.  Using awareness to spot a trap or Intrigue to find out some court gossip are examples of unopposed resolution.  I may modify the necessary roll in some cases to account for factors specific to the attempt.  For instance, a Saxon knight trying to use Intrigue in Earl Robert's halls may get a -5 to the attempt because Hate Saxons is directed trait for people from Salisbury.  Likewise, a knight might get a plus to flirting after a successful courtesy roll.

In general, the GM will roll dice during the year to keep things flowing.  Players can roll their end-of-year advancement, etc.