The hard disk drive (HDD) is an excellent example of the practical application of precision mechatronics. Hard Disk Drive: Mechatronics and Control describes the control aspects of an HDD, explains difficulties faced by designers, provides solutions, and highlights challenges of future-generation drives. Combining academic interests with practical problems, it provides a problem-oriented approach to the fundamental concepts of control, examines the process involved in the manufacturing of HDDs, and illustrates the application of precision mechatronics in great detail. Mechatronics researchers not working in HDD will find many concepts developed that are useful for problems in their own areas.

Magnetic information storage systems plays a very important role in this era of digital information. All computer literate people of the world use these system to save billions of bytes of digital information and to access them as and when required; both of these services are available at the touch of our fingertips. Magnetic hard disk drives constitute the lions share of these storage systems.

The hard disk drive (HDD) industry is slightly more than half a century old. The five decades of this industry have experienced many excellent and triumphant technological innovations. It took creativity and hard work of many scientists and engineers to transfer from the earliest HDD of 1956 to the current status. In comparison to the disk drives we see these days, the earliest disk drive was a monstrous device occupying a large floor. It was used in the system called Random Access Method of Accounting and Control (RAMAC) produced by IBM. Today’s drives are tiny compared to that, however, the storage capacity of the monstrous RAMAC can not even be described by the word tiny. The journey of the HDD industry that began in 1956 is yet to reach its end. The demand for more and more online storage created by the new and developing digital technologies is growing and will continue to grow in the near future. The ability to meet such demand at relatively low cost makes HDD the undisputed candidate for online, direct access, non-volatile storage of a computing system. The HDD industry has so far met successfully the challenges of high density storage at low cost, and it continues to progress at lighting speed. The future demand for online storage of huge digital information brings in promises for this industry as well as new challenges.