Western Digital (WD) has unveiled the first 2 terabyte (TB) hard drive - the world's highest capacity drive and the latest addition to WD's Caviar Green hard drive family. This new 3.5-inch platform is based on WD's industry-leading 500 GB/platter technology (with 400 Gb/in2 areal density) with 32 MB cache, producing drives with capacities of up to 2 TB, the company said in a statement.