Friends

as defined on
friend n.
1. A person whom one knows, likes, and trusts.
2. A person whom one knows; an acquaintance.
3. A person with whom one is allied in a struggle or cause; a comrade.
4. One who supports, sympathizes with, or patronizes a group, cause, or movement: friends of the clean air movement.
5. Friend A member of the Society of Friends; a Quaker

Friendship
1. The state of being friends; friendly relation, or attachment, to a person, or between persons; affection arising from mutual esteem and good will; friendliness; amity; good will.
There is little friendship in the world. --Bacon.
There can be no friendship without confidence, and no confidence without integrity. --Rambler.
Preferred by friendship, and not chosen by sufficiency. --Spenser.
2. Kindly aid; help; assistance, [Obs.]
Some friendship will it [a hovel] lend you gainst the tempest. --Shak.
3. Aptness to unite; conformity; affinity; harmony; correspondence. [Obs.]

There are different degrees to friends/friendship...

the people you call to hang out with, the people who listen to all your problems as you listen to theirs, people who would lay down whatever they're doing to help you in a jam...

Friends are treasures that shouldn't be tossed aside like yesterdays garbage. Friends should be supportive of all you do, even if they think you're a dork for doing it. Friends should always tell you the truth even if it might hurt to hear it, and then be there for you to cry on, after you hear it.

When in need you should be able to run to your friends, not run away from them.

They should be choosen carefully.
If you have been chosen as someones friend you should feel privileged, just as they should feel privileged and honoured to be considered someone elses friend.