Vegetarian cuisine is based on food that meets vegetarian standards by not
including meat and animal tissue products (such as gelatin or
animal-derived rennet). For lacto-ovo vegetarianism (the most common type
of vegetarianism in the Western world), eggs and dairy products (such as
milk and cheese without rennet) are permitted. For lacto vegetarianism,
dairy products are permitted but eggs are not, and for ovo vegetarianism
eggs are permitted but dairy products are not. The strictest form of
vegetarianism is veganism, which excludes all animal products, including
dairy, honey, and some refined sugars if filtered and whitened with bone
char. There are also partial vegetarians (flexitarians), such as
pescetarians who may eat fish but avoid other types of meat.
Vegetarian foods can be classified into several different types:
You can check further info on Wikipedia.