mods:mods are small add ons to your world that can make it funner .They can also give you advantages to points levels  and certain objects.some mods require texture packs in order too see all the detail in the mod you are using.mods are usally free and only require a download to play.to find mods a good website is minecraftmods.com.

texuture: packs are packs that stimulate the way you see certain objects in youre world .they are also free and only need downloads

skins:skins are the clothes and what you where on youre avatar again they are usually free and can be made by the player with a templlate.can be found for free downlaod at the skindex.

maps:maps are worlds created by players that can be worked throgh.mostof these also need texture packs in order to see all the details.