Hadoop
18 essential Hadoop tools for crunching big data
https://www.infoworld.com/article/2606340/hadoop-131105-18-essential-hadoop-tools-for-crunching-big-data.html#slide1
Spark
Apache Spark™ - Unified Analytics Engine for Big Data
https://spark.apache.org/
General
What is Spark - A Comparison Between Spark vs. Hadoop
https://intellipaat.com/blog/what-is-apache-spark/Hadoop vs. Spark: A Head-To-Head Comparison | Logz.io
https://logz.io/blog/hadoop-vs-spark/Five things you need to know about Hadoop v. Apache Spark
https://www.infoworld.com/article/3014440/five-things-you-need-to-know-about-hadoop-v-apache-spark.html