grep multiple words/patterns/strings, and/or condition, use -e or regex

Sometimes we need to use the grep command to find multiple words in one file, or to find multiple words in the same line.

1. Match multiple words in a file and the relationship between them is or.

➜ grep -e “hello” -e “world” test.txt

You can also use the grep regex.

➜ grep -E “hello|world” test.txt

More regular usage: grep regex

2. Match multiple words in one line, and the relationship between them is and

➜ grep -e “hello” test.txt| grep -e “world”