According to contents of vacuoles, classified into following types:
(i)**Sap vacuole:**
It is the most common types of vacuole, occurring in higher plants cells.
(ii)**Protein bodies:**
These are specialized protein storing vacuoles present abundantly in seeds. During germination, the stored proteins in protein are hydrolyzed to amino acids and released into the cytosol for use in protein synthesis.
(iii)**Contractile vacuoles:**
These are special vacuoles help in osmoregulation. They are found in freshwater protozoans, are found in fresh water protozoans, Chlamydomosas (an alga) etc.
(iv)**Food vacuoles:**
Such vacuoles contain ingested food particles. Many lysosomes merge with a food vacuole to form a digestive vacuole orgastriole (e.g. protozoan protists, sponges, coelenterates).
(v)**Gas vacuoles (= Pseudo vacuole):**
Such vacuoles, filled with metabolic gases, are found in some prokaryotes and help them in floating.
