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PROBLEM: Many data files come up with header lines. You want to
proces the data but skip the header lines. The header lines are
are usually identified by a distinct starting character or characters
(e.g. "%" or "#").
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$ cat Rabbits
%Rabbit_Name Rabbit_Index
Parvi 10
Laxmi 5
Tubby 8
Padma 6
Rusty 6

	#Below only data lines are piped to AnalysisProgam 
	#sed, grep, awk can use complex regular expressions 
	#tail requires you to know and specify number of header
	lines

$ sed '/^%/d' Rabbits | AnalysisProgram
	#delete all lines with % as first character

$ sed -n '/^%/!p' Rabbits | AnalysisProgram
	#also possible using two negatives

$ grep -v '%' Rabiits | AnalysisProgram
	#pass through lines which do not have % (anywhere) in the line

$ awk '!/^%/' Rabbits | AnalysisProgram 

$ tail -n +2 Rabbits | AnalysisProgram
	# normal usage is $tail -n 5 Rabbits (last 5 lines) # GNU
	when the number is explicitly "+" then counting is from top
	# Thus $tail -n +2 file means start at the second line