When using a UNIX system it is sometimes necessary to change file permissions. This is done using the CHMOD command. There are two different ways to chmod a file.

FTP: Certain FTP clients such as Cute FTP and WS/FTP Pro allow for a chmoding directly within FTP. To do this you would highlight the file that you want to use, and select from the command menu "change file permissions." There is on option for "manual." This is where you will enter the desired CHMOD. Many other FTP clients will support CHMODing as well, we recommend checking the documentation.

Reasons for CHMODING:
CHMODing files can be done for a variety of reasons. You can CHMOD files to do things such as: mark them executable, give them write permission, restrict access to them, and a variety of other reasons. It is important to note that chmoding is nearly impossible to avoid. If you are trying to run a certain cgi script it could require execute permissions on the script itself, write permissions on a directory, and read on an informational page. Your cgi scripts should contain the proper documentation to inform you of the proper CHMOD's.
The chart below shows examples of different CHMOD's and the permissions associated with them. In most cases, "755" should always be used when configuring a script you've written yourself or located on the web.

Command Meaning
chmod 777 filename The file is available for Read, Write, and Execute for the owner, group, and world
chmod 755 filename The file is available for Read, Write, and Execute for the owner; and Read and Execute only for the group and world.
chmod 644 filename The file is available for Read and Write for the owner, and Read only for the group and world.
chmod 666 filename The file is available for Read and Write for the owner, group, and world.