Direct mail is a broad term that includes the following types of mailed promotions: Institutional direct mail serves to promote the name of the publishing house with no reasonable expectation of sales revenues.
touch (Unix) touch is a standard Unix command-line interface program which is used to update the access date and / or modification date of a file or directory. In its default usage, it is the equivalent of creating or opening a file and saving it without any change to the file contents.
echo is one of the most commonly and widely used built-in command for Linux bash and C shells, that typically used in scripting language and batch files to display a line of text/string on standard output or a file. echo command examples.