I am a rust newbie, in the extreme. I am trying to "define" some data that has several layers, and I am having no success. Here's an example of what I am looking at. In sports there are a lot of statistics that are keep. Lets say baseball. Caps or for emphasis only. So we have the top level, BASEBALL, next we have TEAMS which would probable be a vector, with other fields say date of origin, mascot, and so on. Next layer, COACH with name, years experience, age, next layer, SUBCOACH, a vector also since there would be more than one sub coach, along with age, years of coaching, other areas of expertise. Next layer we'll do PLAYERS. They too would be vectors under the sub coach, they may have other fields too, like age, batting average, year of play, positions played and so on and so on. We see multiple layers here with vectors, strings, and integers, or we'll say multiple data types. I have no idea how to define such a data "structure" in rust. It is not important what the data may be, but how to construct such a layout. Thanks for any and all thoughts. Remember I am a newbie with rust so try not to use definitions I may not understand yet. If you include an example please use all layers not just one or two. I have written a hand full of very small rust programs, and now looking for something a bit larger. Thanks again.