P is the 16th letter of the Latin alphabet.

Semitic Pê (mouth) as well as Greek Π or π (Pi) and the Etruscan and Latin letters that developed from the former alphabet all symbolized /p/, a plosive, unvoiced consonant. Those who speak Arabic usually have difficulty pronouncing this sound; they pronounce like b instead.

Papa represents the letter P in the NATO phonetic alphabet.

P is also:

• In chemistry, P is the symbol for the element phosphorus.
• In complexity theory, P is the set of decision problems solvable in polynomial time on a deterministic Turing machine. See Complexity classes P and NP.
• In physics, p is the symbol for momentum, also for pressure; P for power and polarisation; p is also the symbol for the proton.
• As p, the symbol for the pond, a now obsolete unit of force, see kilopond.
• In units the Pico SI Prefix p stands for pico, P for Peta.
• In symbolic logic, p is often used to denote a proposition as well as q and r.
• In the study of probability, p stands for probability.
• In statistics, the p-value of a given result in an experiment the is result's significance; that is, the probability of observing this result or a more extreme result, by chance alone.
• In computers, P is an operation on a semaphore, used for proces synchronisation.

• pa pb pc pd pe pf pg ph pi pj pk pl pm pn po pp pq pr ps pt pu pv pw px py pz