Practical Electronics/Greek Alphabet

Greek letters are often used in electronics, either for prefixes or to represent values, often if the normal letters run out. LetterNameUsesCapitalLowercaseΑαAlphaΒβBetaΓγGammaΔδDeltaΕεEpsilonΖζZetaΗηEtaΘθThetaGenerally used to denote angles or phase relationshipsΙιIotaΚκKappaΛλLambdaUsually used for wavelength, but can also be used to denote an arbitrary constant.ΜμMuLowercase stands for "micro-", the prefix denoting one millionth. Can also be used to denote an arbitrary constant, usually when λ has been used already.ΝνNuΞξXiΟοOmicronΠπPiLowercase denotes a mathematical constant, 3.14...ΡρRhoLowercase can mean resistivity (not resistance) or density.ΣσSigmaCapital denotes the sum of a series of values.ΤτTau PI multiplied by two (6.2831...)ΥυUpsilonΦφPhiSometimes used for angles or phase relationships, if theta has already been used. Can also represent the Golden Ratio.ΧχChiΨψPsiΩωOmegaCapital denotes "ohms", the unit of resistance. Lowercase can mean the "angular speed" or the rate of change of phase of a signal.