programming lang classifications
1. machine lang
   - CPU understands
   - binary-encoded
2. assembly
   - higher-level
   - symbolic programming
   - mnemonic memory/register names
   - faster to write than machine
   - assembler: assembly --> machine
3. high-level
   - fastest to write
   - e.g. FORTRAN, COBOL, BASIC, Pascal
   - compiler: high-level --> assembly
   - C/ C++ (obj-oriented)
   - OO
     - 1960's Simula
     - Smalltalk
     * Java
       - created by Sun Microsystems