Samus Aran
She's out of this world…
Statistics
Age: It's really hard to tell. Due to being augmented with Chozo (and later Metroid) DNA, Samus appears to be a woman in her early-to-mid-twenties, but this is far from confirmed. She started her training sometime between the age of three and five and, by the time of Metroid Fusion, was probably in her early 30s, but this is largely speculation.Species: At her core, Samus is human. However, thanks to both the Chozo Grey Voice and the Metroid Baby, she is also part Chozo and part Metroid now. This has saved her many times, as it allows her access many pieces of otherwise-inaccessible Chozo tech, as well as saving her from the X parasite.
Location: Samus doesn't have much of a defined 'location' beyond her personal ship. Even this changes as she frequently changes her ship around with the only names given being the unofficial 'Cosmo Liner' and 'Hunter IV.' Also, she has a habit of blowing up ecosystems and planets, which means that very few beach-front housing places would likely want to have her living there…
Family Matters: Samus is not a family person. When she was a small child, Ridley, leading the Space Pirates, assaulted her colony, and killed her parents, Virginia and Rodney Aran. She was then adopted by the Chozo whom were fast on their way to extinction. Once trained, she then departed for Federation Space with the only known 'family' - used in the absolute loosest sense of the word - being a baby Metroid that mistook Samus for being its mother. The Metroid died soon afterwards. As of now, she has no further known relatives.

Main Features: The most defining aspect of Samus is her power armour and the versatility it provides, but on a more basic level, her most defining feature is her adaptability. Samus routinely deals with environments that should easily kill her and foes that far outclass her, yet has survived them all. This often comes from quick adaptation to the on-going situation, or from finding and utilising new pieces of varied forms of technology for victory. She is also, very much so, an explorer and treasure hunter, with much of her survival coming from her ability to find previously unknown resources, hidden away in strange places.
She is also capable physically. Even without her iconic armour, she is very well trained and capable of fighting on her own. This ability may have been played up for her appearance in Smash Bros., but there is no doubt as to her skills and capabilities, regardless.
Clothing: Samus's iconic piece of gear is her Power Suit. The baseline suit is capable of utilising multiple pieces of technology from several different races with zero connection errors. She can utilise Chozo, Luminoth, Federation, and even Space Pirate tech, without too much of an issue. Her primary weapon, the arm cannon, is built in to this suit. Capable of delivering normal, fire, ice, electrical, and even light/dark shots, among others, the arm cannon is no slouch. Additionally, the Power Suit boasts various modes, such as the Screw Attack that can allow for a large amount of jumps, and the Morph Ball mode, which nobody has been able to figure out. Under the Power Suit, Samus has been known to wear several different outfits, ranging from a red top/shorts combo to her 'Zero Suit' - a blue, full-body piece of clothing. It is known for both its practicality and fairly figure-hugging design.
Concept
Originally, Samus was actually more devoid of character than someone like Link or even Doom Guy. Even Mega Man had a more defined persona, as Samus was almost, effectively, an empty shell. However, that was altered with one fateful vote and, in fact, Samus ended up getting some inspiration from Alien, of all things. This can even be seen in the faint theme Samus has of motherhood and family issues compared to what Alien does with certain things… However, that's really about it, as the two series went in radically different directions following that. Oddly, Princess Leia may have also helped inspire her personality… That aside, much of what has happened with Samus, and Metroid in general, appears to have been unique to her.
Appearances
Aside from her mainline series and Smash Bros. appearances, Samus has not had any major roles elsewhere. However, Kid Icarus is a sister-series and has had several… similarities, such as how one enemy design is pretty unmistakably a Metroid. This is even called out in Kid Icarus: Uprising.
Best Appearance
Probably either Super Metroid or Metroid Prime, depending on the particular fan. Both are very different in how they function, though, with one being a 2D Metroidvania-style and the other being a 3D adventure that is a bit more focused on the environment and immersion than other things. Both are considered to be great games, however.
Do Not Mention
Metroid: Other M, at least around Western fans who ended up disliking the game immensely. The upcoming (as of the writing of this article) Federation Force may also end up taking a place beside that title.Additionally, when around Samus herself, it is probably best to not bring up her family. There have been some faint rumours that it was Samus, not Sakurai, who put the foot down and stopped Ridley from joining Smash Bros. as anything more than a stage hazard.

Anything Else?
Despite her few actual appearances outside of her own series, Samus has a stack of cameo appearances. Some prime examples include her outfit in Animal Crossing and appearing in a stage for Dead or Alive: Dimensions, if only to kill Stage Hazard Ridley during the fight.Samus has been directly responsible for at least the extinction of the Metroids and likely Ing, as well. In addition, she has inflicted some very heavy casualties on the Space Pirates and other races, plus has blown up at least one planet. As a result, Samus may have one of, if not the, highest kill counts for any Nintendo character.
It was stated once that Samus was not a woman but, rather, a 'Newhalf,' which can be Japanese slang for a transgendered woman. However, this comment came from a background designer while the series creator has stated that there being a Metroid game on the PS2 was as likely as Samus being a 'Newhalf.'
Despite how Nintendo marketed the N64, there was no Metroid game in the works for it. Since then, she has made various appearances elsewhere.