That was done 10 years ago and it did indeed help on the old slow drives where usually Windows XP ran on. Today modern OSes should defrag automatically (atleast Vista+7+8+10 do it) in the background. Unless you turn it off for vague performance reasons.
NOTE: If you have a SSD, don't do it, as it will unnecessarily wear it out. If you don't know what that is, then you probably don't have one (unless you have a thin laptop, then you might).
In windows 10 (and probably 8/8.1) it doesn't allow you to defrag SSDs, instead it does something else to them (i can't remember the name) that is beneficial for them.
Yea i forgot, Vista and up automatically don't defrag SSDs. SSDs need TRIM for keeping a good performance (and that is also handled automatically). http://www.apartmenttherapy.com/trim-that-drive-why-trim-matte-142681