Vegetarianism is when someone chooses not to eat meat. This can be for a few reasons, like not wanting to hurt animals or thinking that eating vegetables is healthier. Religion is when people believe in a higher power, like God, and follow a set of rules based on their beliefs.
Some religions, like Hinduism and Buddhism, believe in not hurting animals and that all living things are equal. They believe that if you don't eat meat, you aren't hurting animals and are being respectful to all living things. In some religions, like Jainism, people believe in not eating anything that grows underground, like onions or garlic, because they believe it hurts the plants.
In other religions, like Christianity and Islam, there isn't a strict rule about being vegetarian, but some people still choose to be for personal reasons. Some Christians believe that being vegetarian is better for the environment and that it's a way to live more simply, like Jesus did.
Overall, people choose to be vegetarian for different reasons, and sometimes their religions play a part in that decision.