Mexican food peculiarities are well known even for those who has never tasted Mexican food. First of all Mexican cuisine is known for its varied and intense flavors, diversity of spices, colourful decoration and multiplicity of different recipes. But I would make an outline of three main Mexican food peculiarities: diversity, zest and adaptability.
The diversity comes from the rich history of Mexican cuisine. In the 15th century two very powerful food traditions collided: the Mayan-Aztec and the Spanish one. Fortunately neither of them devoured the other, and so Mexican cuisine was born. Mexican food peculiarities vary slightly with the region. Four main regions have their own interpretation of the Mexican traditional food. The region of Veracruz specializes on fish dishes and has experienced a certain influence, of the European cuisine (olives, capers). Puebla is the mother land of sweet, thick mole sauce and appetizing desserts. Yucatan is famous for very (in Mexican understanding) mild sauces, based chiefly on fruits. And Oaxaca is famous for its very particular blend and method of cooking coffee.
Zest of the Mexican food is achieved through the great number of chiles and salsas, which in Mexico are either added to or served with almost every dish. And they of course make up one of the most important Mexican food peculiarities. It is a wide-spread illusion that all the chiles are burning hot, but in Mexico they grow some 140 species of chile peppers, and those chiles have a huge scope of tastes from mild anaheim to raving hot habanero. Salsas (sauces) are usually made of tomatoes, onions, garlic and chiles. These little tasty Mexican food peculiarities add up gusto even to the dullest dishes. They can be of any kind: thick, thin, hot, mild, sweet, fresh, cooked or bottled.
And finally the adaptability of Mexican cuisine proves itself in numerous Mexican restaurants in all parts of the world. Due to the simplicity and sustenance of Mexican recipes they became widely used in fast-foods. A new cuisine has emerged lately, called Tex-Mex: a combination of Mexican and American food.