Inform: With word we can inform other people about our thoughts or opinions.
Manipulate: We can use words to manipulate others to do what we say or accept our opinions.
Express feelings: Whether you like or hate somebody, words can communicate to that person the same feelings.
Negotiation: If you want a better price, I'm sure you can't get it by waving your hands, but when it comes to words, these can change the game's rules.
Likes/dislikes: What we like is different from a person to another and by letting someone know what you like can get you to receiving your dream gift. You can't tell what you like or not properly by using any other measures beside words.
