Ramp load/unload
A plastic ramp at the disk's edge onto which the heads are parked, lifting them clear of the platter instead of landing on it.
In contact start-stop drives the heads land on a dedicated landing zone on the platter — cheap, but a source of stiction and wear. Ramp load/unload, standard in laptop drives since the late 1990s and now near-universal, instead slides the heads up onto a moulded ramp just beyond the disk's outer edge whenever the drive idles or loses power. The heads never touch the recording surface, which eliminates stiction and improves shock tolerance while parked — vital for portable drives. The soft "click" you hear when a laptop sleeps is the actuator parking on the ramp.