Forward-looking: The data storage landscape is evolving rapidly, driven by the proliferation of artificial intelligence and the growing demand for massive data lakes. Western Digital projects that HDD exabyte shipments will grow at a compound annual growth rate of 23% from 2024 to 2028. To meet these increasing demands, the company is focusing on two key innovations that will drive capacity expansion and enhance storage efficiency. Western Digital unveiled an ambitious roadmap for advanced storage technologies at a recent investor day meeting. It plans to leverage two advanced storage technologies in the coming years: heat-assisted magnetic recording (HAMR) and heat dot magnetic recording (HDMR), which are expected to improve data storage efficiency and density in hard disk drives.This announcement comes as Western Digital prepares to separate its Flash business, with the spin-off scheduled for February 21, 2025.HAMR technology uses a small laser diode attached to each recording head to heat a tiny spot on the disk. This localized heating temporarily reduces the coercivity of the recording material, enabling the write head to alter the magnetic polarity of a single bit at a time.By allowing data to be written in much smaller regions, HAMR significantly increases storage density. This technique requires precise temperature control to ensure that only the intended area is heated, with nanosecond-level heating and cooling of individual bits.Western Digital plans to introduce its first HAMR-based HDDs in 2026, with initial capacities of 36TB for conventional magnetic recording (CMR) and 44TB for shingled UltraSMR recording. The company is already testing HAMR drives with two major hyperscale customers. By 2030, Western Digital aims to develop HDDs with capacities ranging from 80TB to 100TB using HAMR technology. // Related StoriesIn parallel, Western Digital is also developing HDMR technology, which combines heat-assisted writing with bit-patterned media (BPM). HDMR has the potential to achieve even higher areal densities, possibly exceeding 8 Tb/inch. This could enable 10-platter HDDs with capacities of 120TB or more.HDMR technology involves physically patterning disks using lithography or etching equipment in cleanroom environments. This process ensures uniform grain size and precise bit placement, resulting in more predictable magnetic properties. The combination of physical isolation of bits with energy-assisted writing enables unprecedented storage densities.However, HDMR is expected to be quite expensive due to its complex manufacturing requirements. The transition to these technologies will necessitate substantial investments, including the development of new types of lasers for highly precise localized heating.Western Digital is focusing on several key areas to support these. This includes refining servo-mechanics for precise head positioning, conducting magnetics research into advanced materials such as iron-platinum alloys, and developing new thermal management and control systems to accommodate the next generation of HDD technology.