Using the command line calendar and date functions in Linux

have always been interested in historical dates and determining the actual day of the week an event occurred. What day of the week was the Declaration of Independence signed? What day of the week was I born? What day of the week did the 4th of July in 1876 occur? I know that you can use search engines to answer many of these questions. But did you know that the Linux command line can supply those answers, too?