I would like to purchase an external hard drive for my computer and I see some that are 1TB and 500GB. Which one has more memory and how much more?
12 Answers

1tb has twice as the 500

External Hard Drive Gb

1TB = 1024 GB
500GB x 2 = 930GB will be read as.
The difference between units based on SI and binary prefixes increases as a semilogarithmic (linearlog) function—for example, the SI kilobyte value is nearly 98% of the kibibyte, a megabyte is under 96% of a mebibyte, and a gigabyte is just over 93% of a gibibyte value. This means that a 300 GB (279 GiB) hard disk is indicated only as 279 GB. As storage sizes increase and larger units are used, this difference becomes even more pronounced.

A terabyte (or Tbyte) is a SImultiple (see prefix tera) of the unit byte for digital information storage and is equal to 1012 (1 trillion short scale) bytes or 1024 gigabytes. The unit symbol for the terabyte is TB.
The designation terabyte is often used to refer to the tebibyte, its binary prefix analogue. Disk drive sizes are always designated in SI units by manufacturers. However, a possible confusion arises from this definition with the longstanding tradition in some fields of information technology and the computer industry of using binary prefix interpretations for memory sizes. Standards organizations such as International Electrotechnical Commission (IEC), Institute of Electrical and Electronics Engineers (IEEE) and International Organization for Standardization (ISO) recommend to use the alternative term tebibyte to signify the traditional measure of 1024^4 bytes, or 1024 gibibytes, leading to the following definitions:
* In standard SI usage, 1 terabyte (TB) equals 1000000000000bytes = 1000^4 or 10^12 bytes.
* Using the traditional binary interpretation, a terabyte would be 1099511627776bytes = 1024^4 = 2^40 bytes = 1 tebibyte (TiB).
The capacities of computer storage devices are typically specified using their the standard SI meaning of unit prefixes, but many operating systems and applications report in binarybased units. Mac OS X 10.6 (Snow Leopard) reports decimal units.

1000 gb

1tb – 1000 gb = 2 x 500 gb
better read a little about oc’s before you start
you will end up with crashed computer in 2 days

1000

Simplified you can say 1 TB = 1000 GB, so 1 TB = 2 x 500 GB

1 TB = 1024 Gb
1024 Gb > 500 Gb

1 TB is almost Double 500Gbs, so 1 TB = 2 500Gbs
1000 GB in Decimal system
1024 GiB in Binary system