Fresh out of the store Mac computer promises flawless experience and the 1 Tb SSD seems to be more than enough. But with time every user faces slowing-down performance that spoils the whole experience. One of the most common reasons for slower Mac is that you get duplicate files that can pack a lion part of your hard drive. Appearing over time among photos, videos and iTunes files, these duplicates can become a real problem. Unless you know how to find and delete them – and here is a brief guide on how to do that.