Iota

Greek alphabet
Α α Alpha	Β β Beta
Γ γ Gamma	Δ δ Delta
Ε ε Epsilon	Ϝ ϝ Digamma
Ζ ζ Zeta	Η η Eta
Θ θ Theta	Ι ι Iota
Κ κ Kappa	Λ λ Lambda
Μ μ Mu	Ν ν Nu
Ξ ξ Xi	Ο ο Omicron
Π π Pi	Ϻ ϻ San
Ϙ ϙ Qoppa	Ρ ρ Rho
Σ σ Sigma	Τ τ Tau
Υ υ Upsilon	Φ φ Phi
Χ χ Chi	Ψ ψ Psi
Ω ω Omega	Ϡ ϡ Sampi

Iota (upper case Ι, lower case ι) is the 9th letter of the Greek alphabet. In the system of Greek numerals it has a value of 10.

Iota is the smallest letter in the Greek alphabet.

The word iota is also used in English to express a very small amount. By some accounts this usage stems from the third- and fourth-century theological dispute over the Arian doctrine that Jesus and God the Father were of distinct but similar substances—Greek homoi-ousios—against the orthodox doctrine that they are one substance—Greek homo-ousios. The two words differ by one iota.

Letters that arose from Iota include the Roman I.