Pills form when short fibres work loose and tangle. Fabrics blending fibres of different strengths pill most, because the weaker fibres break while the stronger ones hold the pill in place.
Reduce it by: washing inside out, washing less often, using a gentler cycle, and avoiding tumble drying.
Remove it with a fabric comb or a battery de-piller, working gently and in one direction. Do not pull pills off by hand — that takes intact fibre with them and thins the fabric.
US/UK: British English says bobbling as often as pilling.