Latex is a sticky emulsion produced by specialized cells called laticifers in plants. It is present in 10% of all flowering plants (angiosperms) and is a complex emulsion that coagulates on exposure to air, consisting of proteins, alkaloids, starches, sugars, oils, tannins, resins, and gums. Latex is usually exuded after tissue injury and serves mainly as defense against herbivorous insects. It is not to be confused with plant sap, as it is a distinct substance, separately produced, and with different functions.

Latex is produced in vessels or special cells called laticifers, single cells, or strings of cells that form tubes, canals, or networks in various plant organs. Plant families that produce copious amounts of latex include the Euphorb family (Euphorbiaceae), milkweed family (Asclepiadaceae), mulberry family (Moraceae), and dogbane family (Apocynaceae). The Brazilian rubber tree, Hevea brasiliensis, which is native to the Amazon Basin and a member of the euphorbia family, is the only commercial source of natural rubber at present.

Latex has many uses, from clothing to paint, but most importantly is rubber. Natural latex, which is nearly chemical-free, is used in the manufacturing of natural latex mattresses, beauty application pads, and cushioning. Latex paint uses synthetic latex as a binder, which is not flammable, has little odor, and cures to form a dry paint film. Latex collected from the rubber tree is where we get rubber.

Latex also contains defensive chemicals, which can be an irritant and lead to an allergic response in some individuals. Prolonged exposure can lead to anaphylactic shock, and individuals with a latex allergy should avoid contact.