Humans have used chili peppers and other hot spices for thousands of years. One of the first commercially available bottled hot sauces appeared in 1807 in Massachusetts. However, of the early brands in the 1800s, few survive to this day. Tabasco sauce is the earliest recognizable brand in the hot sauce industry, appearing in 1868 and becoming synonymous with the term hot sauce. As of 2010, it was the number 13 best-selling condiment in the United States preceded by Frank's RedHot Sauce in number 12 place.
There are many recipes for hot sauces but the only common ingredient is any kind of chili pepper. A group of chemicals called capsaicinoids are responsible for the heat in chili peppers. Many hot sauces are made by using chili peppers as the base and can be as simple as adding salt and vinegar while other sauces use some type of fruits or vegetables as the base and add the chili peppers to make them hot. Manufacturers use many different processes including aging in containers, pureeing and cooking the ingredients to achieve a desired flavor. Because of their ratings on the Scoville scale, Ghost pepper and Habanero peppers are used to make the hotter sauces but additional ingredients are used to add extra heat, such as pure capsaicin extract and mustard oil. Other common ingredients include vinegar and spices. Vinegar is used primarily as a natural preservative, but using flavored vinegars can be used to attain a different taste.
Mexico - Mexican hot sauce typically focuses more on flavor than on intense heat.Chipotles are a very popular ingredient of Mexican hot sauce and although the sauces are hot, the individual flavors of the peppers are more pronounced. Vinegar is used sparingly or not at all in Mexican sauces, but some particular styles are high in vinegar content similar to the American Louisiana-style sauces. Some hot sauces may include using the seeds from the popular achiote plant for coloring or a slight flavor additive. The process of adobos (marinade) has been used in the past as a preservative but now it is mainly used to enhance the flavor of the peppers and they rely more on the use of vinegar. Mexican-style sauces are primarily produced in Mexico but they are also produced internationally. The Spanish term for sauce is Salsa (sauce), and in English-speaking countries usually refers to the often tomato-based, hot sauces typical of Mexican cuisine, particularly those used as dips. There are many types of Salsa (sauce) which usually vary throughout Latin America.
These are some of the notable companies producing Mexican style hot sauce.
United States: Most often called hot sauce, they are typically made from chili pepper, vinegar and salt. The varieties of peppers that are used often are cayenne, chipotle, habanero and jalapeno. Some hot sauces, notably Tabasco sauce, are aged in wooden casks similar to the preparation of wine and fermented vinegar. Other ingredients, including fruits and vegetables such as raspberries, mangoes, carrots, and chayote squash are sometimes used to add flavor, mellow the heat of the chilis, and thicken the sauce's consistency.
Artisan hot sauces are manufactuered by smaller producers and private labelers in the United States. Their products are produced in smaller quantities in a variety of flavors. Many sauces have a theme to catch consumers attention. Some of the notable companies producing these sauces are:
Blair's 16 Million Reserve is certified by the Guinness book of World Records as the hottest product available.
Chili pepper water: Used primarily in Hawaii, this concoction is ideal for cooking. It is made from whole chilies, garlic, salt, and water. Often homemade, the pungent end product must be sealed carefully to prevent leakage.
Sriracha sauce A traditional Thai hot sauce, made primarily of ground chilies, garlic, vinegar, sugar, and salt. Often called "rooster sauce" after the most widely sold U.S. brand's label.
A very mild chili sauce is produced by Heinz and other manufacturers, and is frequently found in cookbooks in the U.S. This style chili sauce is based on tomatoes, green and/or red bell peppers, and spices; and contains little chili pepper. This sauce is more akin to tomato ketchup and cocktail sauce than predominantly chili pepper-based sauces.
New Mexico: New Mexican style chile sauces differ from others in that they contain no vinegar. Almost every traditional New Mexican dish is served with red or green chile sauce. The sauce is often added to meats, eggs, vegetables, breads, and some dishes are, in fact, mostly chile sauce with a modest addition of pork, beef, or beans.
Green chile: This sauce is prepared from any fire roasted native green chile peppers, Hatch, Santa Fe, Albuquerque Tortilla Company, Bueno and Big Jim are common varieties. The skins are removed and peppers diced. Onions are fried in lard and a roux is prepared. Broth and chile peppers are added to the roux and thickened. Its consistency is similar to gravy, and it is used as such. It also is used as a salsa.
Red chile: A roux is made from lard and flour. The dried ground pods of native red chiles are added. Water is added and the sauce is thickened.
West Indies - Hot pepper sauces, as they are most commonly known there, feature heavily in Caribbean cuisine. Like American-style sauces, they are made from chili peppers and vinegar, with fruits and vegetables added for extra flavor. The most common peppers used are habanero and Scotch bonnet, the latter being the most common in Jamaica. Both are very hot peppers, making for strong sauces. Over the years, each island developed its own distinctive recipes, and home-made sauces are still common.
Picante Chombo D'Elidas is a popular brand in Panama, with three major sauces. The yellow sauce, made with habanero and mustard, is the most distinctive. They also produce red and green varieties which are heavier on vinegar content and without mustard.
China. Chinese chili sauces usually come as a thick paste, and are used either as a dipping sauce or in stirfrying.
Dou ban sauce (la dou ban jiang 辣豆瓣醬, la dou jiang 辣豆醬, dou ban jiang 豆瓣醬), ("la" is "spice", "dou" is "bean", "ban" is "piece", and "jiang" is "sauce") originates from Szechuan cuisine in which chilis are used liberally. It is made from broad bean or soybean paste, and usually contain a fair amount of chili. Often referred to in English as chili bean sauce.
Pao la jiao or yu la jiao (泡辣, 鱼辣椒), dipped chili or fish chili, is made by pickling whole, fresh red chilis in a brine solution; this sauce is the key ingredient in the famous Sichuan dish Yuxiang rousi (鱼香肉丝), julienned pork in fish fragrance sauce. The key to this pickle is to add a live crucian carp to the pickling pot along with the chilis, hence the name fish chili. The carp is supposed to lend its fragrance and umami to the pickle.
Chili oil, La jiao You or hong you (辣椒油, 红油), is another distinctive Sichuan flavoring found mainly in cold dishes, as well as a few hot dishes. Chili oil is made by pouring hot oil onto a bowl of dried chilis, to which some Sichuan pepper is usually added. After steeping in hot oil for at least a few hours, the oil takes on the taste and fragrance of chili. The finer the chili is ground, the stronger the flavor (regional preferences vary - ground chili is usually used in western China, while whole dried chili is more common in northern China.)
Guilin chili sauce (Guìlín làjiāojiàng 桂林辣椒酱) is made of fresh chili, garlic and fermented soybeans; it also is marketed as soy chili sauce (la jiao jiang and la dou ban jiang are not the same thing, though they look vaguely similar in the jar).
Duo jiao sauce (duo jiao 剁椒) originates from Hunan cuisine, which is reputed to be even spicier than Sichuan cuisine. Duo means chopped, and jiao means chili. Duo jiao is made of chopped red chilis pickled in a brine solution, and has a salty and sour pickled taste; it is the key flavoring in the signature Hunan dish duo jiao yu tou (剁椒鱼头), fish head steamed with chopped chili.
Sos Cili, a category of its own, uses tomato puree, chili juice, sugar, salt and some other spices or seasonings to give the spicy, but not too hot, taste. Some countryside commercial varieties use bird's eye chili (cili padi, cabai rawit or burung) together with its seeds to raise the level of heat (piquancy) of the sauce. Variants include the typical concoctions with ginger and garlic (for chicken rice) and variants that are made into gummy consistency as with ketchup/tomato sauce.
Phrik nam pla is served with nearly every Thai meal
In Thailand, Thais put raw chilies on a very wide variety of food, in lieu of chili sauces. Chili sauces are eaten as condiments but they can also be used as an ingredient.
Nam phrik is the generic name for a Thai chili dip or paste. Nam phrik phao (roasted chili paste), nam phrik num (pounded grilled green chili paste) and nam phrik kapi (chili paste made with fermented shrimp paste) are some of the more well-known varieties.
Many Thai dipping sauces (nam chim) contain chili peppers. Nam chim chaeo uses ground dried chili peppers to achieve its spiciness. Available worldwide is nam chim kai, also known as "chili sauce for chicken" or "Thai sweet chili sauce".
Phrik nam pla is fish sauce (nam pla) with chopped raw chilies, lime juice and sometimes garlic.
Sriracha sauce is a Thai chili sauce. Shark brand Sriracha sauce is an authentic, classic Thai version, made in Si Racha, Thailand.
Shatta (Arabic: شطة) is a popular hot sauce made from wholly grounded fresh chili peppers by mixing them with oil (usually olive). Vinegar, garlic, or other spices are commonly added. There are two varieties of Shatta: green and red. The red variety is made with tomatoes. It's made from piri piri, or similarly hot peppers. The degree of hotness varies according to the type of chili used and preference of the maker (homemade Shatta is usually hotter than commercial brands). Commonly used in falafel sandwiches, hummus dishes, or as a condiment.
Harissa is a popular hot sauce used in Tunisia. It is usually made from grounded red birdseye chili peppers with olive oil, garlic, cumin and coriander although caraway is sometimes used instead of cumin and recipes vary. The sauce is of a dark red grainy texture. It is sometimes spread on bread rolls but also used as a condiment with a variety of meals. Tunisian Harissa is much hotter than that found in neighboring countries. Cap Bon is a popular brand of Harissa. Harissa is often sold in tin cans.
United Kingdom - Two of the hottest chilis in the world, the Naga Viper and Infinity chilli were developed in the United Kingdom and are available as sauces which have been claimed to be the hottest natural chili sauces (without added pepper extract) available in the world (The Naga Viper and Infinity were considered the hottest two chili peppers in the world until the Naga Viper was unseated by the Trinidad Moruga Scorpion in late 2011.).
Hungary - Erős Pista (lit. "Strong Steve") and Piros Arany (lit. "Red Gold") hot pepper paste, both made from minced hot paprika (Capsicum annuum L.).
Chinese style sauces such as black bean and chili.
The heat, or burning sensation, experienced when consuming hot sauce is caused by capsaicin and related capsaicinoids. The burning sensation is not "real" in the sense of damage being wrought on tissues. The mechanism of action is instead a chemical interaction with the neurological system.
The seemingly subjective perceived heat of hot sauces can be measured by the Scoville scale. The Scoville scale number indicates how many times something must be diluted with an equal volume of water until people can no longer feel any sensation from the capsaicin. The hottest hot sauce scientifically possible is one rated at 16,000,000 Scoville units, which is pure capsaicin. An example of a hot sauce marketed as achieving this level of heat is Blair's 16 Million Reserve (due to production variances, it is up to 16 million Scoville units), marketed by Blair's Sauces and Snacks. By comparison, Tabasco sauce is rated between 2,500 and 5,000 Scoville units (batches vary) - with one of the mildest commercially available condiments, Cackalacky Classic Condiment Company's Spice Sauce, weighing in at less than 1000 Scoville units on the standard heat scale.
A general way to estimate the heat of a sauce is to look at the ingredients list. Sauces tend to vary in heat based on the kind of peppers used, and the further down the list, the less the amount of pepper.
Cayenne - Sauces made with cayenne, including most of the Louisiana-style sauces, are usually hotter than jalapeño, but milder than other sauces.
Chile de árbol - A thin and potent Mexican chili pepper also known as bird's beak chile and rat's tail chile. Their heat index uses to be between 15,000 and 30,000 Scoville units, but it can reach over 100,000 units. In cooking substitutions, the Chile de árbol pepper can be traded with Cayenne pepper.
Jalapeño - These sauces include green and red jalapeño chilis, and chipotle (ripened and smoked). Green jalapeño and chipotle are usually the mildest sauces available. Red jalapeño sauce is generally hotter.
Naga Bhut Jolokia - The pepper is also known as Bhut Jolokia, ghost pepper, ghost chili pepper, red naga chilli, and ghost chilli. In 2007, Guinness World Records certified that the Ghost Pepper (Bhut Jolokia) was the world's hottest chili pepper, 400 times hotter than Tabasco sauce; however, in 2011 it has since been superseded by the Trinidad Moruga Scorpion.
Piri piri - The Peri Peri pepper has been naturalized into South Africa and is also known as the African Bird’s Eye pepper, Piri-Piri pepper or Pili-Pili pepper, depending on what area of the country you’re in. The pepper ranges from one half to one inch in length and tapers at a blunt point. The small package packs a mighty punch with a 175,000 rating on the Scoville scale which is near where the habanero pepper is but the pepper is smaller and has a much different flavor. It is most commonly used in a hot sauce, combined with other spices and seasonings because it has a very light, fresh citrus-herbal flavor that blends well with the flavors of most other ingredients. 
Scotch Bonnet - Similar in heat to the Habanero are these peppers popular in the Caribbean. Often found in Jamaican hot sauces.
Tabasco peppers - Sauces made with tabasco peppers are generally hotter than cayenne pepper sauces. Along with Tabasco, a number of sauces are made using tabasco peppers.
Trinidad Moruga Scorpion The golf ball-sized chili pepper has a tender fruit-like flavor. According to the New Mexico State University Chile Institute, the Trinidad Scorpion Moruga Blend ranks as high as 2,009,231 SHU on the Scoville scale, making it the hottest chili pepper in the world to date.
Capsaicin extract - The hottest sauces are made from capsaicin extract. These range from extremely hot pepper sauce blends to pure capsaicin extracts. These sauces are extremely hot and should be considered with caution by those not used to fiery foods. Many are too hot to consume more than a drop or two in a pot of food. These novelty sauces are typically only sold by specialty retailers and are usually more expensive.
Other ingredients - heat is also affected by other ingredients. Mustard oil and wasabi can be added to increase the sensation of heat but generally, more ingredients in a sauce dilute the effect of the chilis, resulting in a milder flavor. Many sauces contain tomatoes, carrots, onions, garlic or other vegetables and seasonings.
Remedies for pain caused by eating hot sauces or chilis
Capsaicinoids are the chemicals responsible for the "hot" taste of chili peppers. They are fat soluble and therefore water will be of no assistance when countering the burn. The most effective way to relieve the burning sensation is with dairy products, such as milk and yogurt. A protein called casein occurs in dairy products which binds to the capsaicin, effectively making it less available to "burn" the mouth, and the milk fat helps keep it in suspension. Rice is also useful for ameliorating the impact, especially when it is included with a mouthful of the hot food. These foods are typically included in the cuisine of cultures that specialise in the use of chilis. Mechanical stimulation of the mouth by chewing food will also partially mask the pain sensation.
Cooling and mechanical stimulation are the only proven methods to relieve the pain; many questionable tips, however, are widely perpetuated. Since capsaicin in its pure state is poorly soluble in water, but is more so in oils and alcohol, an often heard advice is to eat fatty foods or beverages, assuming that these would carry away the capsaicin. The value of this practice is questionable and the burning sensation will slowly fade away without any measure taken. Milk, however, has been found to work, as seen on the American TV shows Good Eats, MythBusters and Food Detectives.