The professional programmer who is involved in the actual programming of the Hadoop applications is a Hadoop Developer. The job of a Hadoop developer is similar to software developers, but Hadoop developer is responsible to developing Hadoop applications. To become a Hadoop developer, you need to be familiar with the concept of Big Data and how to find the useful information from the data. A Hadoop developer is responsible for operations on data such as storing, transforming, managing, and decoding it to avoid it from being destroyed.
If you want to learn Hadoop, I recommend this Hadoop Certification program by Intellipaat.
You can watch this video on Hadoop Developer to understand more: