sprintf and printf are your huckleberries...

The first argument is the format specification, which is then followed by a list of variables that directly correspond to the "placeholders" specified in the format.

For example,

printf "%05d", 32;  # prints an integer 5 digits wide, with leading ze
+roes, ie. 00032
printf "%32s", 'foo'; # prints the word 'foo' into an area 32 characte
+rs wide
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This doesn't even begin to scratch the surface of what sprint and printf do, but it is a place to start.