What is java ? It is an object-oriented language similar to C++, but with advanced and simplified features. Java is free to access and can run on all platforms . Java is: – Ø Concurrent Ø Class-based Ø Independent What is Java used for? Java has been used in different domains. Some of them are listed below: Banking : To deal with transaction management. Retail : Billing applications that you see in a store/restaurant are completely written in Java. Information Technology : Java is designed to solve implementation dependencies. Android : Applications are either written in Java or use Java API. Financial services : It is used in server-side applications. Stock market : To write algorithms as to which company they should invest in. Big Data : Hadoop Map Reduce framework is written using Java. Scientific and Research Community : To deal with huge amount of data. Components in Java: JVM (Java Virtual Machine