Revision sheet: Introduction to Computer Programming

📋 Course Outline

1. Programming Vocabulary Baseline
2. Computers and Program Responsibility
3. System and Application Programs
4. Binary and Machine Language
5. Three Programming Language Levels
6. Compilation and Interpretation
7. Classification and Exact Instructions

📖 1. Programming Vocabulary Baseline

📝 Essential Points

• Unit 1 is a two-hour lecture with two hours of lecture time and no laboratory work, and students write and compile no code in this unit.

📖 2. Computers and Program Responsibility

🔑 Key Concepts & Definitions

• Computer : A machine that stores data and carries out instructions on that data exactly as given.
• Program : A complete set of instructions that tells a computer how to perform one job.
• Instruction : One single command inside a program.

📝 Essential Points

📌 A computer obeys literally, obeys instructions in order unless told to jump, and never guesses when an instruction has no single definite meaning.

• The programmer is accountable for every instruction a computer carries out, including instructions that were omitted or failed to handle a case.

📖 3. System and Application Programs

🔑 Key Concepts & Definitions

• System program : Keeps the computer itself working by managing memory, files, devices, and processor sharing.
• Application program : Exists to perform a job wanted by the user, such as writing, browsing, or computing a grade.
• Operating system : The main system program that shares memory, processor time, and files among other programs.

📖 4. Binary and Machine Language

🔑 Key Concepts & Definitions

• Binary : A number system that uses only the digits 0 and 1.
• Machine language : Consists of instructions written in binary and is the only language form the processor can execute directly.

📝 Essential Points

• To convert a binary number to decimal, add the place values of the positions containing 1, whose values from right to left are 1, 2, 4, 8, 16, 32, and so on.

📖 5. Three Programming Language Levels

🔑 Key Concepts & Definitions

• Assembly language : Writes machine instructions as short command words such as LOAD, ADD, and STORE, with one word for each machine step.
• High-level language : Written for programmer convenience, with one readable line representing many machine steps.

📝 Essential Points

• Machine-level code is binary for the processor, assembly-level code uses short words for one machine step, and high-level code uses readable statements for several machine steps.

💡 Memory Hook

Machine → assembly → high-level

📖 6. Compilation and Interpretation

🔑 Key Concepts & Definitions

• Translator : A program that turns source written in one language into another language.
• Compiler : Translates the whole source file into machine-ready form before the program runs and produces a machine-code file saved on disk.
• Interpreter : Translates and carries out source code one instruction at a time while the program is running, without saving a translated file.

📝 Essential Points

📌 Compilation is slower to start but faster to run and checks the whole file before execution, whereas interpretation starts immediately but translates during execution and finds an error when its line is reached.

💡 Memory Hook

Whole file first versus one instruction at a time

📖 7. Classification and Exact Instructions

📝 Essential Points

• To make an everyday instruction executable, replace every vague judgment with an exact condition and specify the exact output, such as displaying PASSED when the grade is 75 or more and FAILED otherwise.

📊 Synthesis Tables

Program Families

Family	Primary purpose	Examples
System program	Keeps the machine working and manages resources	Operating system, printer driver, antivirus scanner, file manager
Application program	Performs a task wanted by the user	Word processor, web browser, spreadsheet, school enrollment portal

Translation Methods

Dimension	Compilation	Interpretation
Translation timing	Whole source file before execution	One instruction at a time during execution
Output	Saved machine-code file	Nothing saved
Startup and execution	Slower startup, faster execution	Faster startup, slower execution
Error detection	Whole file checked before anything runs	Error found when the faulty line is reached