PP is the 16th letter of the Latin alphabet.
Semitic P? (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.
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 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.
Words beginning with the letter P, suitable for teaching children the alphabet
- Peter Pan