Most Smartphones and iPods have free ear buds as a standard. However, the quality can be poor as they are leaking a lot of sound and letting in background noise. As a result, you turn up the sound in order to hear the music properly.
Compared to ear buds, headphones put the source of sound farther away from your inner ears. This extra space can protect your eardrums from the strain of listening to direct noise.
Switching from ear buds to headphones could be wise as they isolate the background noise better, enabling you to listen at a lower volume.
It is important to have some good quality ear buds or headphones. Noise-cancelling or sound-isolation headphones block out background noise so you are less likely to turn up the sound volume of your iPod or Mp3 player. These do not need to be very expensive and can be found in most music stores. But remember, you still need to keep the volume down to avoid damaging your ears.