Recipe: Printing text between line numbers/patterns

Print lines from line number M to N
===================================
$ awk 'NR==M, NR==N' filename

$ seq 100 | awk 'NR==4,NR==6' 
4 
5 
6 


Print lines between two pattern matches
=======================================
$ awk '/start_pattern/, /end _pattern/' filename

$ cat section.txt 
line with pattern1 
line with pattern2 
line with pattern3 
line end with pattern4 
line with pattern5 

$ awk '/pa.*3/, /end/' section.txt 
line with pattern3 
line end with pattern4
#It supports regular expression patterns