The “cents” scale is used to present relative pitch values. One octave is divided into 1200 cents; that makes one semitone [from one note to the next on a piano] of the equal-tempered scale 100 cents. So +50 cents would lie exactly half-way to the next [piano] semitone above. It doesn't reflect anything in the natural world; it is just a convenient small division for discussing interval sizes.
[Cents derives from the Latin for one hundred, as in percent.]