1930's Alan Turing first thought about programmable machines that had flexible uses.
1940's First properly flexible computers - programmed in binary 'First Generation Languages', for example '010110100110'.
Early 1950's 'Second Generation Languages' - used simple codes to represent operations, like '02A02' for '2 add 2'.
Converting code to binary
A compiler is used to convert human language code into binary code once. The binary code can then be run as many times as you like.
An interpreter runs the source code directly, usually using its own binary code to complete the tasks asked for.
A brief history of programming cont...
Mid 1950's Third generation languages: in a human readable form, e.g. '2 add 2'.
Fourth generation languages try to let people describe what they want to do, without complicating things with how they're done.
Java is a Third generation 'Object Orientated Language'.
Object Orientated Languages
At first programs were written so all the information about what to do was held in one file, and all the data in another.
Fast became a nightmare.
Object Orientated Languages build bits of code called 'Objects' which can hold data and do specific things with it.
Once they're done, they pass the data on to another Object. Each Object has its own text file associated with it.
Example
Menu fileMenu = new Menu ("File");
MenuItem saveWeb =
new MenuItem ("Save as Web Page...");
fileMenu.add(saveWeb);
MenuListener a = new MenuListener(saveWeb);
Brief History of Java
Java was first released in 1995 as a platform independent and 'nicer' version of C++.
Java 1.1 was released early 1997: Faster. Database access. Networking improved.
Java 1.2 or "Java 2": Slightly fancier.
Java 1.5 / "Java 5" (now 1.7 or "Java 7"): A few additional bits you can turn on.
Java was built by Sun, but they were bought by Oracle.
