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When you were a kid, did you ever make a "telephone" with two tin cans and a long length of string stretched tight between them? You speak into one can, and you voice causes vibrations in the wall of the can. Those vibrations travel down the tight string (it has to be pulled tight) to the other can and vibrate the other can's wall. Then the vibrations make the air vibrate a little, and sound (pretty quiet sound at this point) travels to your ear.
With a vinyl record, the first record players and recorders were basically just a big cone attached to a needle. Someone would talk or sing into a big cone. The cone would vibrate, and the vibrations would be transferred to the needle. The needle would wiggle back and forth into a soft spinning disk (wax I think) and that would make squiggly lines. Then that wax disk would be used as a mold to make in vinyl of the completed record. You could play the record by putting the needle into the groove, and the cone would vibrate. The vibrations would make sound. Pretty cool. I've listened to these old players and they sound surprisingly loud.
Then the players were made electronic to make the music louder. The needle in a record player still fillows the squiggly groove and vibrates, but that vibration makes an electric signal that varies (sort of like vibrating) the signal is strengthened with an electronic amplifier and sent to the speakers. The speakers are coils of wire wrapped around a magnet, with paper cones attached to the wire coil. As the signal goes through the wire coil, the coil moves back and forth in relation to the magnet. This pulls on the paper cone and creates the sound you hear.
Tapes have the electic signal saved to them in a magnetic dust that is applied to the tape. Special heads can read the electric signal (which is a fluctuation in the strength of the magnetic field on the tape) and translate tht into an electric signal that can go to the speakers.
CDs and DVDs put that signal into a digital format of pits in a aluminum foil in a plastic disk. Then a digital processor translates that into an electric signal that goes to the speakers.
I hope this all made some amount of sense to you. :p
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