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![Han Wu](https://secure.gravatar.com/avatar/9128f0eec3ada20dddfd3ec9d248a6b1?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Han Wu
927 PointsWhat happens if private nor public is added?
Throughout the entirety of Java Basics, I have never learned to add these. Am I supposed to?
2 Answers
![David Axelrod](https://uploads.teamtreehouse.com/production/profile-photos/3448142/micro_1513175_4564512968132_59084278236808137_n.jpg)
David Axelrod
36,073 Pointsprotected is another one. These keywords are for security and tell the program what files can access certain variables or classes. For example, if a class is public, it can be used by any file in the directory. However if you have a private variable, it can only be used in the current class or current file
![jason chan](https://uploads.teamtreehouse.com/production/profile-photos/3328982/micro_myself.jpg)
jason chan
31,009 PointsThose are object oriented programming concepts. Public can be called by any object. But private can be only called by only that particular object within the {}.
I hope that helps.
![Han Wu](https://secure.gravatar.com/avatar/9128f0eec3ada20dddfd3ec9d248a6b1?s=60&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Han Wu
927 PointsThanks for the reply.
Han Wu
927 PointsHan Wu
927 PointsOh I see. Thanks