Eiffel is an ISO-standardized, object-oriented programming language designed by Bertrand Meyer (an object-orientation proponent and author of Object-Oriented Software Construction) and Eiffel Software. The design of the language is closely connected with the Eiffel programming method. Both are based on a set of principles, including design by contract, command-query separation, the uniform-access principle, the single-choice principle, the open-closed principle, and option-operand separation. Many concepts initially introduced by Eiffel later found their way into Java, C#, and other languages. New language design ideas, particularly through the Ecma/ISO standardization process, continue to be incorporated into the Eiffel language.