Fifth Letter of the Greek Alphabet. The font "Symbol" most often used on American Computers to Type Cyrillic Letters places it in ASCII 69- the space for capital "E." It looks just like an "E."
Epsilon (uppercase Ε, lowercase ε) is the fifth letter of the Greek alphabet, corresponding phonetically to a close-mid front unrounded vowel /e/. In the system of Greek numerals it has a value of 5. It was derived from the Phoenician letter He .
The change in the price of an option associated with a 1% change in implied volatility(technically the first derivative of the option price with respect to volatility). Also referred to as eta, vega, omega and kappa.
Epsilon is a multi-platform programmers editor that does syntax highlighting, brace matching, etc. It has built-in support for Perl, C, Java, shell scripting, and many other languages.