^ This year I bought the subscription to Safari Books Online (<a href="https:&#x2F;&#x2F;www.safaribooksonline.com" rel="nofollow">https:&#x2F;&#x2F;www.safaribooksonline.com</a>), which offers unlimited access to many books (every O&#x27;Reilly book) and some video courses.<p>Though it&#x27;s not cheap, I think it&#x27;s the best investment I&#x27;ve made in my own professional development.