1. Neuro
1.1. Taste buds
1.2. Olfactory epithelium
2. Glandular
2.1. According to duct and secretory gland
2.1.1. Simple gland
2.1.1.1. Tubular
2.1.1.2. Alveolar
2.1.1.3. Tubule-alveolar
2.1.2. Simple branched gland
2.1.2.1. Tubular
2.1.2.2. Alveolar
2.1.2.3. Tubular-alveolar
2.1.3. Compound branched gland
2.1.3.1. Tubular
2.1.3.2. Alveolar
2.1.3.3. Tubular-alveolar
2.2. According to secration
2.2.1. Nature
2.2.1.1. Mucous
2.2.1.1.1. Goblet cells
2.2.1.1.2. Minor salivary gland
2.2.1.2. Serous
2.2.1.2.1. Parotid glands
2.2.1.2.2. Pancreas
2.2.1.3. Mucoserous
2.2.1.3.1. Submandibular
2.2.1.3.2. Sublingual
2.2.1.4. Sweat
2.2.1.4.1. Watery secretion with enzymes and waste products
2.2.1.5. Oily
2.2.1.5.1. Fatty secretion
2.2.1.6. Waxy
2.2.1.6.1. Ceruminous
2.2.2. Mode
2.2.2.1. Merocrine
2.2.2.1.1. Salivary
2.2.2.2. Apocrine
2.2.2.2.1. Mammary
2.2.2.3. Holocrine
2.2.2.3.1. Sebaceous
3. Covering
3.1. Simple
3.1.1. Squamous
3.1.1.1. Lung aveoli
3.1.1.2. Blood vessels
3.1.1.3. Heart
3.1.1.4. Small ducts
3.1.2. Cubical
3.1.2.1. Renal tubules
3.1.2.2. Medium ducts
3.1.3. Columnar
3.1.3.1. Non modified
3.1.3.1.1. Large ducts
3.1.3.2. Modified
3.1.3.2.1. Secretory
3.1.3.2.2. Absopitive
3.1.4. Pseudo stratified columnar epithelium
3.1.4.1. Non celiated
3.1.4.1.1. Large ducts
3.1.4.2. Ciliated
3.1.4.2.1. Nasal sinuses
3.1.4.2.2. Trachia
3.1.4.2.3. Bronchi
3.2. Stratified
3.2.1. Squamous
3.2.1.1. Keratinized
3.2.1.1.1. Epidermis of the skin
3.2.1.2. Non keratinized
3.2.1.2.1. Mouth cavity
3.2.1.2.2. Ear drum
3.2.1.2.3. Oesophagus
3.2.1.2.4. External auditory canal
3.2.2. Transitional
3.2.2.1. Pelvis of kidney
3.2.2.2. Ureter
3.2.2.3. Urinary bladder
3.2.2.4. Prostatic urethra