I picked up a taste for the Margarita Cocktail when I was in California. I would argue that it is one of the three greatest cocktails of all time alongside the Dry Martini, and the Bloody Mary. There are various theories as to when and how the Margarita was first born. Carlos "Danny" Herrera is said to have first mixed a concoction of white tequila, lemon juice, and Triple Sec in 1938. He was the barman at the Rancho La Gloria in Tijuana, the Mexican border town where the Caesar Salad had been invented by Caesar Cardini.
Essentially, the Margarita is a mix of Tequila (Silver or Blanco tequilas are preferable to the gold), Triple Sec (ie Cointreau), and Lime Juice (or possibly Lemon Juice). The rim of the glass is moistened with lime juice, and then dipped into salt. Some Margarita afficinados claim that salt was only used to hide the taste of a low-budget tequila, but I have to put up my hand and say that I like the contrast between the salt and the sweetness of the tequila and the Triple Sec.
I trawled the net for authentic Margarita recipes and found this one from "Drink of the Month" in the December 1953 issue of Esquire Magazine: 1 ounce tequila Dash of Triple Sec Juice of 1/2 lime or lemon Pour over crushed ice, stir. Rub the rim of a stem glass with rind of lemon or lime, spin in salt—pour, and sip. Again, simplicity rules ok? Nothing frozen. No cocktail umbrellas. No extra ingredients. A Margarita is a Margarita. Got it?