Introduction to Programming Concepts

Overview

This introduction to programming lecture covers the foundational concepts of computer science applicable to any programming language, including key topics like variables, control structures, debugging, and strategies for developing code.

What is Programming?

• Programming is giving computers step-by-step instructions to perform tasks without mistakes.
• Computers only understand binary (machine code) and require precise instructions.
• Programming languages act as intermediaries between human language and machine code.

Programming Languages & Syntax

• High-level languages (like Python, Java) are easier for humans; low-level languages (like C, Assembly) are closer to machine code.
• Syntax refers to the grammar rules for writing code in each language; errors in syntax prevent code from running.
• Each language has unique syntax rules, even for simple operations like defining variables.

Writing, Running, and Debugging Code

• Code is written in an Integrated Development Environment (IDE), which provides tools for writing, running, and debugging.
• The console outputs messages from the program using print statements.
• Syntax errors, runtime errors, and logic errors are common; IDEs help identify and fix them.

Variables and Data Types

• Variables are named containers for storing data; each has a type (int, float, Boolean, string, char).
• Variable names typically use camelCase (e.g., playerScore) for readability.
• Variables can be updated and referenced throughout a program.

Control Structures: Conditionals and Loops

• Conditional statements (if, else if/elif, else, switch) allow code to execute differently based on conditions.
• Loops (for, while, do-while, for-each) repeatedly execute code blocks; important for tasks like iterating through arrays.

Arrays, ArrayLists, and Dictionaries

• Arrays store multiple values of the same type, referenced by index (starting from zero); their size is fixed.
• ArrayLists (or lists) are dynamic arrays with flexible size.
• Dictionaries store key-value pairs, allowing for quick data retrieval using unique keys.

Searching Algorithms

• Linear search checks each element sequentially; works on unsorted lists but is inefficient.
• Binary search splits sorted lists to quickly find values; much more efficient than linear search.

Functions and Recursion

• Functions are named blocks of code that can take arguments and return values; they improve code organization and reusability.
• Functions can be imported from libraries or written by the programmer.
• Recursion is when a function calls itself, useful for breaking problems into smaller parts.

Debugging Strategies

• Use print statements and breakpoints to trace errors.
• Comment out code to isolate the source of bugs.
• Backup code frequently and test changes in small increments.

Pseudocode and Planning

• Pseudocode helps plan programs without worrying about syntax.
• Methods include flowcharts, step-by-step writeups, and feature/function hierarchy outlines.

Choosing a Programming Language

• Select a language based on your project (e.g., HTML/CSS for websites, Python/Java for general purposes).
• Get comfortable with one language’s syntax and then branch out as needed.

Next Steps in Learning

• Research potential languages and choose one that fits your interests.
• Learn the language through tutorials and practice on coding challenge sites (e.g., CodingBat, Coderbyte, HackerRank).
• Enroll in programming courses or join programming communities for further learning.

Key Terms & Definitions

• Programming Language — Human-readable set of rules for instructing computers.
• IDE (Integrated Development Environment) — Software for writing and managing code.
• Variable — Named storage for data in a program.
• Syntax — Grammar rules for writing code.
• Array — Fixed-size list of elements of the same type.
• Dictionary — Collection of key-value pairs for efficient data lookup.
• Function — Reusable block of code that may take inputs (arguments) and return outputs.
• Loop — Structure that repeats code multiple times.
• Recursion — A function calling itself to solve subproblems.
• Debugging — Finding and correcting errors in code.
• Pseudocode — Informal code-like description used for planning algorithms.

Action Items / Next Steps

• Research and select a programming language to learn.
• Watch beginner tutorials for your chosen language.
• Practice coding on platforms such as CodingBat, Coderbyte, or HackerRank.
• Plan your programs with pseudocode before coding.
• Take relevant programming classes if available.