@SquidneyBean you sir are either a total moron or new to minecraft.
Texture pack is the old name of the now known ressource pack. A texture pack has only 1 image for all the block textures in the game, terrain.png. A ressource pack has individual image for every texture in the game, and supports custom music and sound effects.
First yawp its *resource pack
A texture pack allows you to only change the actual textures of blocks and guis etc
A resource pack allows youto not only edit the textures but animate them too, as well as add more than one texture to a block. You can edit sounds but thats pretty boring. Also you can edit block models, if i want stone to have the block model of an anvil, bam done. And lastly you can add/change the language files.
Shameful advert incoming I made a resource pack (hint hint click click) http://www.planetminecraft.com/texture_pack/doomblah-15/