Watch the following video - this shows how Moby took the sampled piece, found the material he needed, and altered it for use in Porcelain.
The clip above shows how one small section of a piece can become the foundation for another piece. Here, Moby has sampled a pre-existing piece of music and turned the small sample into a loop. The loop has then become the chord progression for the entire of 'Porcelain'.
Sampling, using loops, and creating chord progressions, come under the musical concept of STRUCTURE.
The 'Porcelain' chord progression opens the song followed by a staggered entry of instrumental layers, altering the TEXTURE.
These instruments include two layers of percussion (drum machine), a keyboard, vocalisation, strings, and the song melody. Most of these have been manipulated electronically, enhancing the TONE COLOUR of each instrument.
Many pop pieces today use techniques such as these. You may even be able to recognise which original song has been sampled (for example Rihanna's 'Don't Stop the Music' clearly samples Michael Jackson's 'Wanna be Startin' Something').