Ask the Experts / Export plug-in

I have been playing from the early years of RCT. Would someone explain what the checkbox labeled "Export plug-in object with saved games" does?

It includes custom scenery objects that you've included in the park in the save game. if that's not checked, all it keeps is essentially an ID code signifying the object used; if it is checked, the game will pack the object and all included sprites in with the save file, which will make the file substantially larger, but will make sharing a lot more difficult, if you used any custom objects. General best practice is to uncheck it when building, if (and you should) you increment your saves, and then check it for any saves you make that you expect to share. We require that submissions to the site are properly exported.

thanks