How to identify a weed?

Could you please elaborate on the process of identifying a weed? What specific characteristics should one look for when trying to distinguish between a weed and a non-weed plant? Is there a specific method or tool that is commonly used to aid in this identification process? Additionally, are there any common misconceptions or mistakes that people often make when trying to identify weeds? Lastly, are there any resources or guides that you would recommend for someone who is looking to improve their ability to identify weeds accurately?