learning linux recovery disk (the first week)

Linux Introduction:

First, remember that a person

Linus Torvalds: Linux father

User documentation and rights management:

There is a very interesting numbers: 7
Read: R & lt (4 represents a)
Write: W (with 2 represents)
execution: X (with a representative)

For example, if only to read and write permission, execute permission is not given, then by 6 (2 + 4) represents; If only just read permission, write permission is not given, then with 5 (4 + 1) represents. 4,2,1 In short, is that you can easily add will not be heavy.