Vacuoles are the large, sac-like organelles that are used for storage and other functions within the cell. They are similar to, but distinct from, the vesicles, which are tiny sacs that help transport chemicals within the cell.
Vacuoles are a major structural part of plant and fungal cells, though they are also sometimes found in animal cells. In plants and fungi, vacuoles store water to keep the cell rigid. They also store nutrients and food for later use. Sometimes vacuoles are used to store pigments, as in many flower petals, or to store noxious chemicals that poison grazers, as in foxglove.
In animal cells, vacuoles are smaller and often not even present. Animal cells use vacuoles to remove waste and take in valuable compounds, though they may also be used for storage, just like in plants. Vacuoles in animals are, for the most part, a larger version of the tiny vesicle.