The best invent: Digital Music

Digital audio refers to technology that records, stores, and reproduces sound by encoding an audio signal in digital form instead of analog form. Sound is passed through an analog-to-digital converter (ADC), and pulse-code modulation is typically used to encode it as a digital signal. A digital-to-analog converter performs the reverse process, and converts the digital signal back into an audible sound. Digital audio systems may include compression, storage, processing and transmission components. Conversion to a digital format allows convenient manipulation, storage, transmission and retrieval of an audio signal.

Why do I prefer it? 

The music is very important to mankind, It has medical effects, reduce the cortisol which means less stress, and a who doesn't like listenning music? There's a URL, what you can see my reasons:

http://www.muyinteresante.es/salud/articulo/siete-cosas-que-no-sabias-sobre-los-efectos-de-la-musica (this URL is in spanish)

And you can go wherever you want, and listen music anytime!