And they aren't nearly as costly per gigabyte as they once were. They are more energy efficient, more reliable and quieter than hard drives with magnetic, spinning disks. There's a reason that all modern MacBooks and the vast majority of all laptops sold today use SSDs. If you have an old MacBook Pro with one foot in the grave, the single best thing you can do to breathe new life into it is replace its traditional spinning hard drive with a solid-state drive.
