Learning how to become a data scientist has became much more accessible due to the availability of online courses. The following is a list of free resources to learn different skills online:

• Udemy—Learn Java Programming From Scratch at https://www.udemy.com/learn-java-programming-from-scratch.
• Udemy—Java Tutorial for Complete Beginners at https://www.udemy.com/java-tutorial.
• LearnJAvaOnline—Interactive Java tutorial at http://www.learnjavaonline.org.

Some online courses to learn more about machine learning are as follows:

• Coursera—Machine Learning (Stanford) by Andrew Ng: This teaches you the math behind many machine-learning algorithms, explains how they work, and explores why they make sense at https://www.coursera.org/learn/machine-learning.
• Statistics 110 (Harvard) by Joe Biltzstein: This course lets you discover the probability of related terms that you will hear many times in your data science journey. Lectures are available on YouTube at http://projects.iq.harvard.edu/stat110/youtube.
• Data Science CS109 (Harvard) by John A. Paulson: This is a hands-on course where you'll learn about Python libraries for data science, as well as how to handle machine-learning algorithms at http://cs109.github.io/2015/.