programming languages

• What are the two classifications of programming languages?

  Low-level and high-level languages
• What are the two types of low-level languages?

  Machine-code and assembly language
• What is an imperative high-level language?

  A language that uses commands for the computer
• What are the advantages of machine-code programming?

  Direct control over hardware and performance
• What are the disadvantages of assembly language programming?

  Complexity and difficulty in debugging
• Who developed the Colossus computer?

  Tommy Flowers
• What was the input method for the Colossus computer?

  A continuous loop of paper tape
• What was the purpose of the Colossus computer during WWII?

  To break the Enigma Code
• What type of cipher did the Enigma Code use?

  A Vernam-type cipher
• What was the memory cell technology used in early computers?

  Vacuum tubes
• What is the structure of a typical machine code instruction?

  Opcode and operand
• How many different instructions are possible using 8 bits for the opcode?

  256 different instructions
• What does the instruction '0000' do in machine code?

  Load value into the accumulator
• What does assembly language improve upon compared to machine code?

  Uses mnemonics for opcodes
• What is the meaning of the instruction 'LDA' in assembly language?

  Load value into the accumulator
• What is the relationship between assembly language and machine code?

  One-to-one correspondence between instructions
• What was the first high-level programming language?

  FORTRAN
• How do high-level languages differ from low-level languages?

  They allow abstraction from hardware details
• What is an example of an imperative high-level language?

  C#
• What is the purpose of translating high-level language statements?

  To convert them into machine code
• What is a disadvantage of high-level languages compared to low-level languages?

  Object code may run slower
• Why are high-level languages considered portable?

  They can be recompiled for different computers
• What was the memory capacity of the Apollo 11 computer?

  64KB
• How has computer technology evolved since 1943?

  Significantly improved in hardware and software
• What are the three types of program translators?

  Assembler, compiler, interpreter
• What is the role of an assembler?

  Translates assembly language into machine code
• What is the role of a compiler?

  Translates high-level language into object code
• What is the role of an interpreter?

  Executes high-level language programs statement by statement
• What is the difference between compilation and interpretation?

  Compilation translates; interpretation translates and executes
• Why are programs still written in assembly language?

  For speed and direct hardware access
• What is the relationship between assembly language and machine code?

  One assembly statement maps to one machine code statement
• What is the relationship between high-level programming language and machine code?

  One high-level statement maps to several machine code statements
• When would it be preferable to use a compiler?

  When speed of execution is critical
• When would it be preferable to use an interpreter?

  When rapid debugging is required
• What does an assembler do?

  Translates assembly language into machine code
• What does a compiler produce?

  A separate independently executable object code
• What is bytecode?

  An intermediate language between machine code and high-level language
• Why is bytecode produced by some compilers?

  For execution on a virtual machine
• How does a bytecode interpreter work?

  It parses and executes bytecodes one at a time
• What is the advantage of using bytecode?

  It is portable across different platforms