: Proprietary ChessBase formats. You will need ChessBase or the free ChessBase Reader to view these. What to Expect in the Content
Since the file ends in , it is a high-compression archive. You will need a specific utility to open it: Extract the Files : Windows : Use 7-Zip (free/open-source) or WinRAR. Mac : Use The Unarchiver or Keka. Mobile : Use the iZip or ZArchiver app. Identify the File Formats Inside : J Ferien PartienTaktikfragen 7z
The name translates to likely curated for students or club players to study during school breaks. How to Access and Use the Guide : Proprietary ChessBase formats