A stream can be considered as a sequence of bytes travelling from a source to a destination.

All input and output data transfer in Java happens through streams.

There can be different types of sources and destinations such as disk files, input devices like keyboards and even other programs, and there are different stream classes available corresponding to each of these types of sources and destinations.

HTTP Server

Internet is a global system of interconnected computer networks that connect various Domain Name System (DNS) servers, web hosting servers, home and business users, etc. Internet is a network of networks.

Internet Protocols

Lot of data transfer happens in an internet between computers and networks, and there should be some rules to regulate these transfers. A communications protocol is a system of digital rules for data exchange within or between computers.

Let us do a simple hands on excercise followed by some questions to understand exceptions better. For theory and concetps of exceptions in Java. you can refer to the note introduction-to-exceptions-in-java. 

Exercise

Create a class MyClass and create three methods myMethod1(), Method2() and Method3().

Invoke Method2() from Method1() and Method3() from Method2().

Cloud computing can be considered as a business model that delivers resources such as computing and storage, on demand, using technologies such as server virtualization. On demand simply means using only when needed. In simple terms, cloud or on demand means using a resource installed on some server over internet when needed, rather than installing and using the software from your machine. Instead of buying a resource paying the complete price, you can now use the resources on cloud, paying only fraction of the price; and the price is based the actual usage.