Answer:
I am the word that is always spelled correctly by everyone.
In all the world none can compare I am a tiny weaver my deadly cloth so silky and fair.
I am the tool for inspiring many. Buy me in the store for not much more than a penny. Don't overuse me, or my usefulness will go. What am I?
Use me if you really want to see inside someone
I come in different colors and shapes. Some parts of me are curvy, some are straight. I look like I can belong anywhere but there is only one right place for me. What am I?
No matter how little or how much you use me, you change me every month.