Too Long; Didn't Read
Coursera, Udemy, edX and Udacity courses offer course completion certificates. Author of a popular Java blog and an [educator] often receive questions about the value of these courses. Almost 90% of people who join an online course never complete them. A course completion certificate doesn't make you an expert, but it does show that you have completed a course on a particular subject, and you are a constant learner, an essential attribute while hiring Programmers, Engineers, Developers, and [Data Scientists].