• Machine language  (0 as off, 1 as on) 
  Generally consist of strings of numbers (ultimately reduced to 1s and 0s) that instruct computers to perform their most elementary operations one at a time.
  Machine dependent—a particular ma-chine language can be used on only one type of computer.
  example:   +1300042774
             +1400593419
             +1200274027
• Assembly languages
  Englishlike abbreviations that represent elementary operations formed the basis of assembly languages.
  Translator programs called assemblers convert assembly-language programs to machine language.
  example:  load    basepay
        add     overpay
        store   grosspay
• High-level languages: need compiler to convert them to machine language.
  example:   grossPay = basePay + overTimePay

Compiling a high-level language program into machine language can take a considerable amount of computer time.
Interpreter programs execute high-level language programs directly, although slower than compiled programs run
Java uses a clever mixture of compilation and interpretation to run programs

C Þ C++ Þ Java     C, C++ for system software;
Java garnered the attention of the business community because of the phenomenal interest in the web
C  is a Structure Programming;
C++ =   C & Object-Oriented Programming (OOP)
Java is an Object-Oriented Programming (OOP)
 

• Very high-level languages:  Database (SQL language)
• Natural languages   (English, Chinese, etc.)