make: Echoing
5.2 Recipe Echoing
==================
Normally 'make' prints each line of the recipe before it is executed.
We call this "echoing" because it gives the appearance that you are
typing the lines yourself.
When a line starts with '@', the echoing of that line is suppressed.
The '@' is discarded before the line is passed to the shell. Typically
you would use this for a command whose only effect is to print
something, such as an 'echo' command to indicate progress through the
makefile:
@echo About to make distribution files
When 'make' is given the flag '-n' or '--just-print' it only echoes
most recipes, without executing them. 
Summary of Options Options
Summary. In this case even the recipe lines starting with '@' are
printed. This flag is useful for finding out which recipes 'make'
thinks are necessary without actually doing them.
The '-s' or '--silent' flag to 'make' prevents all echoing, as if all
recipes started with '@'. A rule in the makefile for the special target
'.SILENT' without prerequisites has the same effect (Special
Built-in Target Names Special Targets.). '.SILENT' is essentially
obsolete since '@' is more flexible.
Info Catalog
make: Recipe Syntax
make: Recipes
make: Execution