History of computer language development (mainly meaning more stronger)
The first generation of computer language
Binary manner (using a computer code directly, without any conversion)
Second-generation computer language
Assembly language (solve human can not read the language of the machine, instead of the binary for reverse engineering, such as: cracking software; robots, virus)
Moore's Law (intel company co-founder Gordon Moore)
When the price unchanged, to accommodate the number of transistors on an integrated circuit, about every 18 months will be doubled, the performance will also be doubled, in other words, every dollar can buy computer performance will be every 18 May more than double
Third-generation computer language (high-level language)
Generally divided into: process-oriented and object-oriented two categories
A typical process-oriented language C language, C ++, JAVA is a typical object-oriented language
Various languages:
C language, C ++ language, JAVA language (C ++ -), C # language (C sharp), Python, PHP, JavaScript, etc.
Empire of the birth of Java
C&C++
Born 1972 C
Close to the hardware, run very fast, very efficient
Operating systems, compilers, databases, network systems
Pointers and memory management
C ++ was born in 1982
Object-Oriented
Compatible with C
Graphics field, games, etc.
1995Java birth (process briefly, from the name of the C ++ - or Oak)
C like syntax
No pointer
No memory management
True portability, write once, run everywhere
Object-Oriented
Type safety
And other high-quality libraries
Java Virtual Machine JVM (Java platform running)
Java was born
1995 web graphics program (Applet)
Java is ready to explore and expand:
Java 2 Standard Edition (J2SE): to occupy the desktop
Java 2 Mobile Edition (J2ME): to dominate the mobile phone
Java 2 Enterprise Edition (J2EE): to occupy server
Based on enterprise Java developers a huge number of platforms, systems, tools
Building tools, application servers, Web developers, development tools (intellij idea), etc.
In 2006: Hadoop (Big Data field), Java enter the field
In 2008: Android (phone segment), Java enter the field
Java Features and Benefits
Simplicity, object-oriented, portable, high-performance, distributed, dynamic (reflection), multi-threading, security, robustness,
Three versions of Java
具有write once（编写一次）、run anywhere（运行在任何地方）
JavaSE：标准版（桌面程序，控制台开发....）
JavaME：嵌入式开发（手机，小家电....）
JavaEE：E企业级开发（web端，服务器开发....）
JDK、JRE、JVM（JDK包含JRE包含JVM）
JDK：Java Development Kit （JAVA 开发工具）
JRE：Java Runtime Environment （JAVA 运行环境）
JVM：JAVA Virtual Machine （虚拟机类似于CPU处理相关JAVA的东西）