A printf statement causes output when a program is run.

printf("My favorite color is %s", color);

The information in the Format String (the part
enclosed in double quotation marks) is literally printed
out as output.  Where the %s Format Character is
situated within the Format String, the value of a specific
string is output.  The argument AFTER the Format String 
shows what specific value this will be: the value of the 
variable color.