In a single night of observation the VST (VLT Survey Telescope), which recently started operation in Cerro Paranal, can accumulate over 100 gigabytes of data, thanks to the efficiency with which it scans the southern sky. If we consider the four VLT and VISTA, also located at Cerro Paranal, and all other telescopes spread around the world, we realize that the amount of data that is being acquired in a year can be measured in petabytes (one petabyte is equivalent to a million gigabytes), and is likely to continue increasing with an expected growth rate of a factor of 2 every year.