Electronically Stored Information (ESI) is located within all of our devices. Depending upon who has access to our accounts, and where the information is stored, information can end up in the strangest of places, as the latest probe into the Clinton emails has proved.

While many have called into question how such a large amount of ESI data could be reviewed in such a short period of time, in a matter of days, the answer is quite simple. As reported by Rebecca Shabad of CBS News, those familiar with eDiscovery explain the process as follows:

 “This is not rocket science,” Jonathan Zdziarski, a forensics expert who’s consulted for law enforcement, told Wired. “Eight days is more than enough time to pull this off in a responsible way.”

The technology news outlet also interviewed an anonymous former FBI forensics experts who said the agent reviewed larger collections of data even faster than the current case.

“You can triage a dataset like this in a much shorter amount of time,” the agent told Wired, according to the report. “We’d routinely collect terabytes of data in a search. I’d know what was important before I left the guy’s house.”

The former agent also said that the FBI has tools that can sift out classified documents, which the agent said is similar to software used to detect plagiarism.

Both sources told Wired that investigations can filter out emails by targeting “to” and “from” as well as filtering out duplicates.

The review of the emails found in the new batch found that most were duplicates, CBS News confirmed Sunday.

“The Department of Justice and the FBI dedicated all necessary resources to conduct this review expeditiously,” a Justice Department spokesperson said in a statement.