Interesting options tha could be added:
Show line number while displaying the output using grep -n
Show only the matched string -o
Counting the number of matches using grep -c
Display the lines which does not matches all the given pattern. -e
grep -e "pattern" -e "pattern"
Invert match using grep -v
Displaying lines before/after/around the match using grep -A, -B and -C
Checking for full words, not for sub-strings using grep -w