About laptop hard drives

With a wide range of portable computers -- laptops, netbooks, tablets, etc. -- manufacturers come up with better and cheaper ways of storing data internally. Laptop hard drives come in many sizes, and you need to know what they offer to match your needs. The most important factors to take into account are: the type of drive, its capacity, speed and data transfer rates.

Hard-Disk Drive

• Hard-disk drive (HDD) is still the most common type of laptop drive. HDDs are similar to the hard drives used in desktop computers but are smaller and usually slower. The slowest ones, which spin at 4,200 rpm, tend to have more capacity; the faster ones (5,400 or 7,200 rpm) usually have smaller capacities and tend to be more expensive. The faster the drive, the quicker your laptop can access data.

Solid-State Drives

• Unlike "traditional" hard-disk drives, solid-state drives (SSD) have no moving parts but instead rely on solid-state memory modules. It makes them quieter and less fragile than hard-disk drives as they don't rely on memory platters. However, they have lower capacity than hard-disk drives and tend to be more expensive. Some users prefer SSD despite the price as they tend to be much faster than conventional drives, are more reliable and have lower power consumption, which is very important for portable devices such as laptops.

Capacity

• In July 2009, a one-terabyte (1,000 gigabytes) laptop hard drive was announced by Western Digital. However, most laptops still rely on hard drives of up to 500GB. The biggest solid-state drives also tend to hold up to 512GB.

Price

• SSDs are still significantly more expensive than HDDs, although more and more manufacturers are using them in their laptops, netbooks and tablets.

Manufacturers

• The most popular HDDs are manufactured by five large companies: Western Digital, Seagate, Toshiba, Hitachi and Samsung. More companies are producing SSDs, among them SanDisk, Seagate, WD, Intel and Fusion-io.