The modern Greek alphabet consist of 24 characters. Even for those of us with minimal or no exposure to the Greek language, we do come across the alphabet as it is used in many branches of science and mathematics.

A few short notes:

• The lower case sigma, has 2 variants. The symbol, ς, is used only at the end of words while the symbol, σ, is used elsewhere.
• There isn't a standard way of entering the Greek characters into your keyboard. Many variables exist, such as the type of font used, the operating system and software application so that what works for you might not work for another.
• What I have found that works quite well is to simply search for the character that you want on the web, and do a copy and paste.
• If you are using a html editor, using the Html entity works too.

Finally, I have to apologise for the slight fomatting issues as the editor I'm using does not suppose tables.

The Greek Alphabet

Name: Alpha
Upper Case: Α.......Unicode (Hex): U+0391.......HTML Entity: Α
Lower Case: α.......UniCode (Hex): U+03B1......HTML Entity: α

Name: Beta
Upper Case: Β.......Unicode (Hex): U+0392.......HTML Entity: Β
Lower Case: β.......UniCode (Hex): U+03B2......HTML Entity: β

Name: Gamma
Upper Case: Γ.......Unicode (Hex): U+0393.......HTML Entity: Γ
Lower Case: γ.......UniCode (Hex): U+03B3......HTML Entity: γ

Name: Delta
Upper Case: Δ.......Unicode (Hex): U+0394........HTML Entity: Δ
Lower Case: δ.......UniCode (Hex): U+03B4.......HTML Entity: δ

Name: Epsilon
Upper Case: Ε.......Unicode (Hex): U+0395........HTML Entity: Ε
Lower Case: ε.......UniCode (Hex): U+03B5........HTML Entity: ε

Name: Zeta
Upper Case: Ζ.......Unicode (Hex): U+0396........HTML Entity: Ζ
Lower Case: ζ.......UniCode (Hex): U+03B6.......HTML Entity: ζ

Name: Eta
Upper Case: Η.......Unicode (Hex): U+0397........HTML Entity: Η
Lower Case: η.......UniCode (Hex): U+03B7........HTML Entity: η

Name:Theta
Upper Case: Θ.......Unicode (Hex): U+0398........HTML Entity: Θ
Lower Case: θ........UniCode (Hex): U+03B8.......HTML Entity: θ

Name: Iota
Upper Case: Ι.........Unicode (Hex): U+0399........HTML Entity: Ι
Lower Case: ι.........UniCode (Hex): U+03B9.......HTML Entity: ι

Name: Kappa
Upper Case: Κ........Unicode (Hex): U+039A........HTML Entity: Κ
Lower Case: κ........UniCode (Hex): U+03BA........HTML Entity: κ

Name: Lambda
Upper Case: Λ........Unicode (Hex): U+039B........HTML Entity: Λ
Lower Case: λ........UniCode (Hex): U+03BB.......HTML Entity: λ

Name: Mu
Upper Case: Μ.......Unicode (Hex): U+039C.........HTML Entity: Μ
Lower Case: μ........UniCode (Hex): U+03B1........HTML Entity: μ

Name: Nu
Upper Case: Ν........Unicode (Hex): U+039D.........HTML Entity: Ν
Lower Case: ν........UniCode (Hex): U+03BD........HTML Entity: ν

Name: Xi
Upper Case: Ξ........Unicode (Hex): U+039E.........HTML Entity: Ξ
Lower Case: ξ........UniCode (Hex): U+03BE........HTML Entity: ξ

Name: Omicron
Upper Case: Ο.......Unicode (Hex): U+039F.........HTML Entity: Ο
Lower Case: ο.......UniCode (Hex): U+03BF........HTML Entity: ο

Name: Pi
Upper Case: Π........Unicode (Hex): U+03A0........HTML Entity: Π
Lower Case: π........UniCode (Hex): U+03C0.......HTML Entity: π

Name: Rho
Upper Case: Ρ........Unicode (Hex): U+03A1........HTML Entity: Ρ
Lower Case: ρ........UniCode (Hex): U+03C1.......HTML Entity: ρ

Name: Sigma
Upper Case: Σ........Unicode (Hex): U+03A3........HTML Entity: Σ
Lower Case: σ.......UniCode (Hex): U+03C3.......HTML Entity: σ
Lower Case: ς........UniCode (Hex): U+03C2.......HTML Entity: ς

Name: Tau
Upper Case: Τ........Unicode (Hex): U+03A4........HTML Entity: Τ
Lower Case: τ........UniCode (Hex): U+03C4.......HTML Entity: τ

Name: Upsilon
Upper Case: Υ........Unicode (Hex): U+03A5........HTML Entity: Υ
Lower Case: υ........UniCode (Hex): U+03C5.......HTML Entity: υ

Name: Phi
Upper Case: Φ.......Unicode (Hex): U+03A6........HTML Entity: Φ
Lower Case: φ.......UniCode (Hex): U+03C6........HTML Entity: φ

Name: Chi
Upper Case: Χ.......Unicode (Hex): U+03A7.........HTML Entity: Χ
Lower Case: χ.......UniCode (Hex): U+03C7........HTML Entity: χ

Name:Psi
Upper Case: Ψ.......Unicode (Hex): U+03A8........HTML Entity: Ψ
Lower Case: ψ.......UniCode (Hex): U+03C8.......HTML Entity: ψ

Name: Omega
Upper Case: Ω.......Unicode (Hex): U+03A9........HTML Entity: Ω
Lower Case: ω.......UniCode (Hex): U+03C9.......HTML Entity: ω