CD readers and burners
How can a CD-ROM drive in a PC accurately read (or write) particular bits on the surface of a CD, even while the computer is in use, being typed on, possibly being moved around, etc.? Isn't the structure used to represent an individual bit remarkably tiny in comparison to the vibrations produced by typing (let along picking up an operating laptop), or the macroscopic imperfections produced by wear and stress on the CD drive tray? How can the CD-ROM aim and focus accurately at the level of an individual bit given all the mechanical noise enveloping the system?
