The salivary glands produce saliva through a system of ducts which makes them exocrine glands (secretes into a duct). We have three paired major salivary glands (parotid, submandibular, and sublingual) as well as hundreds of minor salivary glands which can be classified as serous, mucous or seromucous (mixed).
They do more than predigestion and act as a specialized chemical tagging system that orchestrate removal of harmful substances entering the body. Failure of this system can result in an increased burden to the rest of the detoxification organs, such as the liver, and may result in reactions such as allergies, inflammation, and recurrent illness patterns.