Vegetarianism is when people choose not to eat meat or any other animal products. It has been around for a long time, even before we knew what it was called.
Thousands of years ago, people in countries like India and Greece decided that they did not want to eat animals. Some of them believed that it was wrong to kill animals for food, while others thought that it was unhealthy. In some religions, like Hinduism and Buddhism, vegetarianism is still very important today.
In the 19th and 20th centuries, vegetarianism became more popular in other parts of the world, especially in Europe and North America. Some people became vegetarians for health reasons, while others did it for ethical reasons, like not wanting to support the cruelty of factory farming.
Today, there are many different types of vegetarians. Some people still eat dairy products and eggs, while others do not. Some people only eat fish and seafood, which is called pescatarianism. There are even some people who follow a vegan diet, which means that they do not eat any animal products at all, including honey and gelatin.
So, in short, vegetarianism has been around for a very long time, and it is a way of eating that some people follow for a variety of reasons, such as health or ethical beliefs.