Grep

match any character	.	grep l..n filename	finds 'lynn' or 'loan'
match only if at the beginning of a line	^	grep ^day filename	finds 'day into night'but not 'Some day'
match only if at the end of the line	$	grep day$ filename	finds 'One fine day'but not 'Monday is good'
search for '.' or '^' or '$' in a file	\	grep \* filename	finds '*****1.05'
search for a set of names	[]	grep [dog,dil]bert filename	finds 'dogbert' and 'dilbert'
find all lines that start with an alphabetic character in upper or lower case	^[]	grep ^[A-Z,a-z] filename