Terabytes are multiple single bytes for digital data storage. It is a unit of storage capacity of storage devices. Prefix Terra in international single system means 1012 , so 1 terabyte is 100,000,000,000 bytes or 1 trillion or 1000 gigabytes. 1 terabyte 0.9095 tebytes in binary prefix , or 931.32 gigabytes. The unit symbol is TB or TByte . But Tb means terabit.