One gigabyte of storage cost $228 in 1998 and costs about 88 cents today. A gigabyte holds about 7 minutes of a HD TV movie.
A terabyte is 1,024 gigabytes. The first terabyte hard drive came out in 2007. In May 2009, Yahoo! Groups had 40 terabytes of data to index.
There is an even larger scale these days, petabytes. One petabyte is 1,024 terabytes. A petabyte holds 13.3 years of HD TV movies. To provide more perspective, Google processes an average of about 20 petabytes of data per day. Finally, 50 petabytes is equal to the entire written history of mankind from the beginning of recorded history. What's next? An exabyte is 1024 petabytes.