Herbivores are animals that only eat plants. They are herbivorous animals including humans.
Humans are believed to be omnivores, because they eat meat as well as vegetable matter. However, research has shown that humans are more suited to a herbivore or frugivore diet because of the shape and make up of our hands, feet and teeth. People who eat mostly plants are usually called vegetarians or vegans.
The diets of some herbivorous animals change with the seasons. In the temperate zones of the Earth, some seasons are hot and some are cold, so different plants are available at different times of the year.