What are the differents of these two words?

AUTHOR:
-An author is a person that creates written work.
-eg. books, stories, articles, short or long fiction or nonfiction, poetry or prose, technical or literary.
-Within the copyright law, the word "author" is often used for the creator of any work, be it written, painted, sculptured, music, a photograph or a film, these can be done in individual or in a group (cooperatively).

WRITER:
-The term writer can apply to anyone who creates a written work, but the word 'writer' is use on those who write creatively or professionally more, or the people who have written in many different forms.
-Skilled writers demonstrate skills in using language to portray ideas and images, whether producing fiction or non-fiction stories. The word 'writer' can also be used in music... like composing music...
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i did hw on this before so i kinda got the idea from wikipedia