Whoever newly heard this terminologies they always getting confusing with what is Big data and What is Hadoop?. Whether both are same or which one is subset of another one.
During Java invented and it came into market, It was called as “Programming Language JAVA”. Since that time C, C++ programming language was very famous and it was entirely spread across the software field. However after JAVA becomes famous now a days nobody called it as “Programming language JAVA”. Instead of just they are saying “Java”
Wherever huge data involved, there we are calling as “BIG DATA”. The massive data involved in Data ware housing, Data Analyzing, Data visualization..here it is calling as Big Data tools. So, Big data a common word like programming language. Hadoop is eco-system (group of framework like Map reduce, Hive, Pig, sqoop, Flume, Oozie and etc) under the Big Data.
Hope another one or two years everyone understand Hadoop and they will be never calling as Big data Hadoop, instead will call as “Hadoop”