Overview of Computer Programming and Software Engineering

Computer Programming

Planning, writing, testing, and documenting code to perform tasks.

Software Engineering

Applying math, engineering, and management to reduce costs and complexity, increase reliability, and modifiability; used in large projects.

Computer

50 million instructions/second

iPhone

40,000 instructions/second

Human

Can write ~20 instructions/day

Application Programmers

Work on productivity apps (e.g., MS Office).

System Programmers

Develop system software (OS, drivers, security modules) for servers and mainframes.

Apps

Can take over a year and cost $250,000+.

Problem Statement

Defines elements to manipulate to achieve a goal; includes assumptions and known info.

Assumption

Accepted truth needed to proceed with programming.

Known Information

Data given to help solve a problem.

Predictive Methodology

Extensive upfront planning/documentation.

Agile Methodology

Flexible development and changing specs.

Program Statement

Smallest unit directing computer actions.

Keyword

Predefined command word, can combine with parameters.

Text Editor

Basic text tasks (Notepad, TextWrangler).

Program Editor

For writing code.

VDE (Visual Development Environment)

Specialized for parts of programs.

Runtime Error

Program can't execute a statement.

Logic Error

Incorrect formulas, flawed problem definition.

Syntax Error

Grammar rules of programming language broken.

Debugging

Finding and fixing errors.

Remarks (Comments)

Make code easier to understand.

Performance

Must be acceptable, verified with tests.

Usability

Easy to learn and operate.

Security

Uses formal methods, threat modeling, defensive programming.

Formal Methods

Mathematical, logical models for software verification.

Threat Modeling

Identify vulnerabilities, assets, threats, and mitigation strategies.

Defensive Programming

Anticipate and handle possible errors (walkthroughs, input filtering).

Abstraction

Simplifies by hiding lower-level hardware details.

Low-Level Language

Little abstraction, hardware-focused (specific CPU/microprocessor).

High-Level Language

Human-like syntax (e.g., BASIC, Java, C++).

First Generation

Machine languages (very prone to errors).

Second Generation

Assembly languages (one-to-one CPU commands).

Op code

The operation itself.

Operand

Data or address involved.

Third Generation

Easier commands (COBOL, Fortran, BASIC, C).

Fourth Generation

Database languages (SQL, RPG).

Fifth Generation

Declarative logic programming (Prolog).

Source Code

Human-readable.

Compiler

Converts entire program to object code at once (creates standalone file).

Interpreter

Converts and executes line-by-line (no standalone file).

Scripting Languages

Distributed as readable source code, slower.

SDK (Software Development Kit)

Language-specific tools: compiler, editor, documentation, debugger, APIs.

IDE (Integrated Development Environment)

Single sleek tool (Editor + Compiler + Debugger); Example: Xcode.

Procedural Paradigm

Solving problems through sequences of steps.

Algorithm

Set of ordered steps to perform a task.

Pseudocode

High-level, language-agnostic representation.

Flowchart

Diagram of program flow.

Object-Oriented Paradigm

Solves problems with objects and classes.

Class

Template for objects.

Inheritance

Pass attributes from superclass to subclass.

Class Hierarchy

Organizes classes with inheritance.

Method

Defines an action (uses parentheses).

Polymorphism

Allows methods to be redefined in subclasses.

Encapsulation

Hiding object internals ("black box").

Declarative Paradigm

Describes the what of the problem, not the how.

Prolog Concepts

Facts: Basic information.

Rules

Relationships between facts.

Predicate(argument)

Basic format.

Goal

Prolog searches for answers.

Instantiation

Assigning a value to a variable.

Prolog Rules Structure

Head, Body, and a connecting symbol.

Decision Table

Shows specific rules for multiple conditions and their outcomes.

Extra Key Facts

More than 8,000 programming languages exist, but only ~600 are established.