Probably one of the main features of MacBook Air is the usage of a solid state drive. It’s expensive, but it’s faster and more reliable than a hard drive mechanism. SSDs use high density Flash RAM chips to store data in place of a conventional HDD’s magnetically read platters. SSD includes both Flash RAM chips and an ATA interface, so the computer treats the device just like a hard drive. Upgrading from the Air’s standard 80GB HDD to a 64GB SSD costs a steep $999. The biggest downside after cost is the drop in capacity. Formatted, the 64GB SSD has a capacity of 55.6GB. In disk reading and particularly random access reads, the SSD was dramatically faster: as much as 18 times faster. That means faster booting, faster application launching, and faster open file operations. SSD read speeds won’t make the overall system dramatically faster all the time, but they are noticeable any time a lot of data is being read.