My site runs a wiki tool that can send out regular notification emails about recent changes. I think I can work out the values of the crontab line I need to have, but I don't know where to place the file itself, nor how to create it except by FTP upload.
How do you create a crontab file? Is it just a plain text file like .htaccess? In which directory should it be located in order to be "active"? What chmod value should the file have?