The Ferengi built their entire culture on pursuit of wealth. They are always looking for ways of earning money and rarely turn down a business opportunity - legal or otherwise. In fact the Ferengi's first Grand Nagus (leader), Gint, wrote a business philosphy known as the Rules of Acquisition that up until the Borg war was THE way of life for Ferengi.
Contact with the Ferengi was first made in the year 2355, and culminated in a battle between a Ferengi ship and the USS Stargazer, under the command of Capt. Jean-Luc Picard. However, they remained a mystery until regular contact was established a little less than a decade later in 2364. In that short time, they have stopped being an enigma and have become a regular feature wherever money is to be made in the Federation.
Males are generally the only member of this species to be encountered, because Ferengi women are still in extremely subservient positions. Ferengi males are still shocked by the fact that Federation women wear clothing. They always prefer to deal with males while doing business. They do not live in the same place as their women.
They regard humanoid women as sex objects, and have an extreme lecherousness regarding beautiful women and sex. Often, they can be coerced to give up better judgement in return for the promise of sexual pleasure with a beautiful woman. This pleasure is often in the form of Oo-mox, a stroking of the Ferengi male's ear ridges.
Though highly intelligent, there are almost no Ferengi scientists, and no formal schooling system in their culture. Lessons on handling business deals are handed down from father to son. Almost any technological advancement that Ferengi have benefitted from has been bought or traded for from other cultures.
Ferengi have an odd honor system. They feel that cheating and stealing are acts of cunning, and that anyone who was a victim of their scams was not smart enough to protect themselves from them.
The Ferengi are considered ugly by almost all cultures in the Federation, but these traits give them many advantages. Their oversized ears give them very acute hearing, and their four-lobed brains are non-psionic enough to give them psionic resistance. This gives them protection against mental attacks, especially telepathic attacks. This is a definate advantage for Ferengi, especially when cutting business deals with telepathic races such as Betazoids. No Ferengi can ever possess psionic abilities.
Also, the higher gravity of their homeworld affords them a higher base strength. Even with this added strength, the Ferengi believe it is easier to run away from a fight than to risk injury. A Ferengi who is or has been in the Ferengi military service will have a forehead tattoo.