A black tie event actually has just as much to do with your suit as it does with your tie.
The only test is whether you wear what is right. To get that right, you just need to check before you dress. There is no memorization required. Black tie events mandate a black colored necktie - and that is not your favorite Black Sabbath necktie, either. For this event it is time to break out the penguin suit. You wear your full tux, with dinner jacket, trousers, tux shirt with wing collar, black bow tie, cummerbund, the lot.
Some fashion historians and designers claim that midnight blue is an acceptable alternative. It is worth a shot, as long as you commit to it. When the event is a white tie event, however, it is time to get out even more than the full tux. Your tie must be white in both cases (one that you tie yourself is infinitely preferable to a clip on), as must your waistcoat or vest, a crucial addition to this look. As well, your coat had better have coat tails, and it had better not be so short that your vest pokes out from beneath.
Often, the event will have a tag line, which means that a tie of black color is preferred, but it is optional. White tie events are always ultra formal. Do not expect to see white tie creativity any time soon. As for the variations on a black-tie event, however, each phrase means something different. 'Black tie preferred' tips you off to the fact that if it is easier for you to get a nice suit than a tux, and we mean a nice suit, then take a deep breath, vote yourself confident, and do it. Do not let this be a cop out for looking good.
If you can wear the full black-tie attire, then you should. 'Black tie optional' gives you a little more breathing room, but do not dress down further than you would for a formal wedding. When it comes to events labeled as 'black tie invited', you are generally looking at a larger crowd with fewer restrictions. You will feel as at home in either a suit or a tux. If you can second guess what the main guests will be wearing, then you have definitely got a leg up on the fashion tower.
When it says 'creative black-tie' or 'black-tie creative', it is just that. The Texas style wants cowboy boots and a Stetson, even denim jeans at times. Usually, this means that a black shirt can be substituted for the white shirt, eliminating the need for the tie. If you want to break out the red tie, well, do not say that we let you do it. Usually, if you are going to that sort of an event, then you probably have a better expectation of it than we do anyway. Remember, if the only guideline is just 'black tie', then they are talking about a bow tie, so break out the tux.
If the invitation says that it will be a formal event, then you can usually assume that they mean that a black colored tie is required. 'Semi formal' or 'after five' is when the suits are allowed to come out. It is safest to stick to a dark suit, especially if the dress code is business formal. 'Cocktail attire' means the same as informal. However, you might get away with a lighter suit at an informal gathering. 'Dressy casual' means that it is time to break out the khaki, but it is still best to keep a sports coat on hand. Never, unless the event is specifically labeled as casual, should jeans or a t-shirt be considered.