More and more people are choosing to not eat animals: many for reasons of health, some are ethically or environmentally motivated.
Being vegetarian or vegan is no longer niche. It is becoming increasingly mainstream - polling from 2016 shows there are in excess of half a million vegans in the UK, a number that is expected to rise.
Despite this burgeoning interest, some people aren't sure what the two options involve - and what the differences are.
Broadly speaking, vegetarians simply do not eat animal flesh. The Vegetarian Society defines a vegetarian as follows: "A vegetarian is someone who lives on a diet of grains, pulses, legumes, nuts, seeds, vegetables, fruits, fungi, algae, yeast and/or some other non-animal-based foods (e.g. salt) with, or without, dairy products, honey and/or eggs.
"A vegetarian does not eat foods that consist of, or have been produced with the aid of products consisting of or created from, any part of the body of a living or dead animal. This includes meat, poultry, fish, shellfish, insects, by-products of slaughter or any food made with processing aids created from these."
There are different types of veggies: lacto-ovo will eat both eggs and milk, ovo will eat eggs, and lacto will eat dairy products, but not chicken's eggs. Pescatarians will ditch meat like beef, pork and chicken - but still eat fish. Generally, this is where vegetarianism ends.
Veganism is not a diet, but a moral position - perhaps better defined as a philosophy. The definition given by The Vegan Society is: "Veganism is a way of living which seeks to exclude, as far as is possible and practicable, all forms of exploitation of, and cruelty to, animals for food, clothing or any other purpose."
Where vegetarianism can - and often does - end at simply omitting animal flesh from the diet, veganism is a moral objection to the use, abuse and exploitation of animals.
For this reason, vegans not only omit animals and their secretions from their diets, they also avoid wearing animal products (for example, leather, wool and silk) and avoid using any products that have been tested on animals, or contain animal byproducts. For example, a vegan would avoid using a lipstick that contains beeswax. They will also avoid supporting the use of animals in entertainment (for example, in circuses).
Many vegans consider dairy production to be even less ethical than meat production. In order to produce milk, cows must be pregnant. They are usually artificially impregnated. Once they give birth, their calves are removed - causing great distress to the mother and baby.
According to Government data, around 95,000 bull calves (male calves) are killed at or around birth. This is because they industry cannot profit from them, as they don't produce milk, and so they are seen having no value at all.
After cows have gone through this cycle several times, they are sent to slaughter. It is a system that depends on exploiting the female reproduction system, and causing physical and emotional harm to animals.
Egg production is also systematically cruel, relying on the mass killing of animals.
As males do not lay eggs - and are therefore of no financial value to producers - they are killed, often by gassing or by being thrown live into a shredder.
The fate of females is even worse: they are kept in often grim, crowded stressful conditions, laying eggs until they are no longer profitable, at which point they too are sent to slaughter.
Another phrase that is becoming more common is plant-based - what does this mean?
Plant-based pertains specifically to diet. In its purest definition, a plant-based diet is limited to plant foods (like a vegan diet) but in addition, plant-based dieters often limit their intake of processed foods and fats, choosing to eat this way for health.
A plant-based dieter is not necessarily vegan, as you can follow this diet, without adhering to the moral framework of veganism.
Vegan or vegetarian?
For many people, vegetarianism is a step on the journey to veganism - it's not always an overnight switch, and many like to slowly implement changes to their diet and lifestyle.
For others, they may care deeply about animals, but be unaware of the barbaric practices within the dairy and egg industries (which are generally kept hidden from public view).
But making the transition to a vegan lifestyle can be personally fulfilling, as well as kinder to animals and the environment. Actor and advocate Alicia Silverstone summed it up best, when she said: "I can’t think of anything better in the world to be but a vegan."