Beginner guide - http://lifehacker.com/5976912/a-beginners-guide-to-diying-with-the-raspberry-pi

Cool! http://blog.afkham.org/2013/02/building-raspberry-pi-cluster-part-2.html

christmas-lights-with-java-and-raspberry-pi - https://www.javaadvent.com/2020/12/light-up-your-christmas-lights-with-java-and-raspberry-pi.html

Monitor air quality with a Raspberry Pi - https://www.raspberrypi.org/blog/monitor-air-quality-with-a-raspberry-pi/