(with a handful of exceptions) designated using Greek letters as serial numbers. The founding chapter of each respective organization is its A chapter. As an organization expands, it establishes a B chapter, a Γ chapter, and so on and so forth. In an organization that expands to more than 24 chapters, the chapter after Ω chapter is AA chapter, followed by AB chapter, etc. Each of these is still a "chapter Letter", albeit a double-digit letter just as 10 through 99 are double-digit numbers. The Roman alphabet has a similar extended form with such double-digit letters when necessary, but it is used for columns in a table or chart rather than chapters of an organization. Glyph variants Some letters can occur in variant shapes, mostly inherited from medieval minuscule handwriting. While their use in normal typography of Greek is purely a matter of font styles, some such variants have been given separate encodings in Unicode. The symbol ("curled beta") is a cursive variant form of beta (β). In the French tradition of Ancient Greek typography, β is used word-initially, and is used word-internally. The letter delta has a form resembling a cursive capital letter D; while not encoded as its own form, this form is included as part of the symbol for the drachma (a Δρ digraph) in the Currency Symbols block, at U+20AF (₯). The letter epsilon can occur in two equally frequent stylistic variants, either shaped ('lunate epsilon', like a semicircle with a stroke) or (similar to a reversed number 3). The symbol ϵ (U+03F5) is designated specifically for the lunate form, used as a technical symbol. The symbol ("script theta") is a cursive form of theta (θ), frequent in handwriting, and used with a specialized meaning as a technical symbol. The symbol ("kappa symbol") is a cursive form of kappa (κ), used as a technical symbol. The symbol ("variant pi") is an archaic script form of pi (π), also used as a technical symbol. The letter rho (ρ) can occur in different stylistic variants, with the descending tail either going straight down or curled to the right. The symbol (U+03F1) is designated specifically for the curled form, used as a technical symbol. The letter sigma, in standard orthography, has two variants: ς, used only at the ends of words, and σ, used elsewhere. The form ("lunate sigma", resembling a Latin c) is a medieval stylistic variant that