1. Program: The term program from life, usually refers to the completion of the process and an established way certain things.
Program can be described as the process of a series of actions to perform.
2. Computer Language: a language for communication between people and computers, it is mainly composed of a number of instructions, the instructions including content Oh numbers, symbols and the like grammar, programmers
These instructions directing the computer through a variety of work.
3. Computer Language Category:
(1) machine language
(2) assembly language
(3) high-level language
Machine language can recognize only the language machine language.
Machine language is encoded by the binary 0 and 1. It is not easy to recognize and remember.
Assembly language identifier using the abbreviation, easy to recognize and remember.
High-level language, close to the natural human language programming to further simplify the process of writing programs, so the name is the choice for most high-level language programmer.
JRE and JDK overview:
A: What is the JRE
* including the required Java Virtual Machine (JVM Java Virtual Machine) and core libraries and other Java programs,
If you want to develop a good run Java programs, the computer can only be installed JRE.
* JRE: JVM + class library.
B: What is the JDK
the JDK (java Development Kit java development kit
* JDK is available to Java developers, which contains the java development tools, including the JRE so installed JDK, do not need to install a separate JRE up. .
* where development tools: compiler tools (javac.exe) packaging tool (jar.exe), etc.
* JDK:. JRE + JAVA development tools
C: Why JDK contains a JRE
* Why JDK contains a JRE it?
* End of program development, we need to run it and see the effect.
D: the role of JDK, JRE, JVM and relationships
A: What is cross-platform
B: the principle of cross-platform Java language
* as long as the operating system needs to run java applications, install a Java Virtual Machine (JVM Java Virtual Machine) can be. By the JVM is responsible for running Java programs in the system.
C: Java language, cross-platform graphical
* write once, run anywhere (a compile, run everywhere)!