A snack is a small portion of food generally eaten between meals.Snacks come in a variety of forms including packaged snack foods and other processed foods, as well as items made from fresh ingredients at home. Snack foods are typically designed to be portable, quick, and satisfying. Processed snack foods, as one form of convenience food, are designed to be less perishable, more durable, and more portable than prepared foods.

They often contain substantial amounts of sweeteners, preservatives, and appealing ingredients such as chocolate, peanuts, and specially-designed flavors (such as flavored potato chips).

In the United States, a popular snack food is peanuts. Peanuts first arrived from South America via slave ships and became incorporated into African-inspired cooking on southern plantations. After the Civil War, the taste for peanuts spread north, where they were incorporated into the culture of baseball games and vaudeville theater.

Along with popcorn (also of South American origin), snacks bore the stigma of being sold by unhygienic street vendors. The middle-class etiquette of the Victorian era (1837–1901) categorized any food that did not require proper usage of utensils as lower-class. Traditional crackers are called krupuk, made from bits of shrimp, fish, vegetables or nuts, which are usually consumed as a crunchy snack or an accompaniment to meals.

These crispy snacks are sometimes added to main dishes for their crunchy texture; several Indonesian dishes such as gado-gado, karedok, ketoprak, lontong sayur, nasi uduk, asinan and bubur ayam are known to require specific types of krupuk as toppings. There are wide variations of krupuk available across Indonesia. The most popular ones would be krupuk udang (prawn crackers) and krupuk kampung or kerupuk putih (cassava crackers). 

Government bodies, such as Health Canada, recommend that people make a conscious effort to eat more healthy, natural snacks, such as fruit, vegetables, nuts, and cereal grains while avoiding high-calorie, low-nutrient junk food. A 2010 study showed that children in the United States snacked on average six times per day, approximately twice as often as American children in the 1970s.

This represents consumption of roughly 570 calories more per day than U.S. children consumed in the 1970s. In the Middle East, one of the most important snacks that contains a huge amount of proteins is Lupinus, commonly known as lupin. Lupin contains around 33-40% protein.Another common snack in the Middle East is hummus made of chickpeas. 

Another one is a Snack cakes are a type of baked dessert confectionery made with cake, sugar, and icing. Snack cakes can be found in many American supermarkets and convenience stores, sold either individually or by the box. Examples include Drake's Devil Dogs, Twinkies and zebra cakes. Well-known American manufacturers of snack cakes include Hostess, Little Debbie, Dolly Madison, Tastykake and Drake's.

In 2004, the snack-cake industry in the US experienced major consolidation, which resulted in fewer products being offered to consumers. For example, Dolly Madison zingers, Hostess brand Twinkies, and Drake's coffee cakes were all solely produced by the now-defunct Interstate Bakeries Corporation.