What is the function of " Flash Fill" in Excel 2013?

The series of entries appear in the new column, literally in a flash (thus, the name Flash Fill), the moment Excel detects a pattern in your initial data entry that enables it to figure out the data you want to copy. The beauty is that all this happens without the need for you to construct or copy any kind of formula.

https://support.office.com/en-us/article/Video-Flash-Fill-9837ec4f-b45b-4c03-af6d-ff900c202032?ui=en-US&rs=en-US&ad=US