Understanding permissions on an Apache server

Understanding permissions on an Apache server: "664 -rw-rw-r-- Read
Write Read
Write Read
775 -rwxrwxr-x Read
Write
Execute
Read
Write
Execute
Read
Execute
755 -rwxr-xr-x Read
Write
Execute
Read
Execute
Read
Execute
744 -rwxr--r-- Read
Write
Execute
Read Read
"

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