Isildur's Heir, Strider, Elessar, the Dúnedan...

Who is Aragorn?  Aragorn is a slightly awesome (well, okay, completely awesome) character.  He also goes by the name of Strider and happens to be the true king of all Middle-Earth. 
This by itself is pretty exciting and if that was all there was to Aragorn, I would probably still like him.  But there’s so much more to his character.

For one thing, he’s wise and powerful.  He has an amazing elfin sword, he knows the Elven tongue and he has a very large amount of knowledge at his command.  Plus, he knows the ways of battle and he’s a good strategist.

For another, he has a sense of humor.  Who can deny that with this quote?
Gimli: It's true you don't see many dwarf women. And in fact, they are so alike in voice and appearance, that they are often mistaken for dwarf men.
Aragorn: [whispering] It's the beards.
-The Two Towers (2002)

I knowww...Aragorn can smile?! ;P

One of the most admirable aspects of his character, in my opinion anyway, is the way he treats Eowyn.  He’s not oblivious to her love (like Marius), nor does he prattle on about his love in her presence (again, like Marius).  Instead, he delicately lets her know that his heart is engaged elsewhere.  Also, he feels for her, as he says himself:
“Few other griefs amid the ill chances of this world have more bitterness and shame for a man's heart than to behold the love of a lady so fair and brave that cannot be returned.”
-Aragorn, The Return of the King

But he’s not completely faraway from all things material- he loves Arwen with all his heart.  He tries to urge her not to give up her immortality for him, but when she does it anyway, I know that he’ll do his best to protect and provide for her as long as they both live.
He's extremely brave, even in the face of death or disgrace. When his little armies are faced by the huge forces of Sauron, he goes forward anyway, after doing his best to make sure the women and children of Gondor are protected. He's willing to sacrifice anything for the safety and peace of Middle-Earth.

However, he’s not exactly perfect either. He makes mistakes and can be reckless and foolhardy.  He doesn’t always make the best choices and he’s slow to trust. He can be proud and disdainful of help.

“My friends. You bow to no one.”
-The Return of the King (2003)
Aragorn can also be humble, and he always respects true worth. For example, when he is crowned King of Middle-Earth, he could have easily forgotten the Fellowship of the Ring. Instead, he honors and praises them, and he actually kneels down before Frodo and Sam because of what they've done.

“If by my life or death I can protect you, I will. ”
-J.R.R. Tolkien, The Fellowship of the Ring

He's loyal; he'd give up his life for any member of the fellowship. He'd prevent evil from befalling anyone in Middle-Earth if he could, which brings me to another aspect of his character: he's self-sacrificing. He would-- and does-- try to protect any random stranger he happened to meet if they were in danger (assuming, of course, that they aren't a minion of Sauron), and he'd be prepared to lay down his life for them. Although he's reserved, he can also be warm and friendly, and easily wins people's hearts (including mine, obviously).

Aragorn is one of my favorite characters in LotR. He's a very worthy king and man, with a good heart and a keen mind. He always tries to protect the people he loves and destroy evil. He's tactful and chivalrous as well as merciful.

And that's Aragorn.