Making Worlds Come Alive

Unity Game Development Course — Week 3: Objects, Components, and Physics

Week 3

Let’s share out our projects!

Welcome Back!

Last week we downloaded all prerequisites, explored the Unity interface, navigation, and how to set up your first project.

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Today we level up! We'll dive into GameObjects, Components, and Physics, learning how Unity brings game worlds to life with structure and behavior.

How Unity Thinks

Project & Scenes

GameObjects

Components

A Project contains Scenes, each Scene is a level or environment where your game takes place.

Every object in a Scene is a GameObject, a container that holds behaviors and properties.

Components are attached to GameObjects to give them abilities: physics, visuals, scripts, and more.

The Transform Component

Every GameObject in Unity has a Transform component by default, it cannot be removed. Transform controls three key properties: Position (where the object is in 3D space), Rotation (which direction it faces), and Scale (how big or small it is). Mastering Transform is essential to placing and moving objects in your scene.

Components Are Superpowers

Attach & Enable

Mix & Match

Built-in Components

Custom Scripts

Add components to any GameObject to instantly give it new abilities.

Combine multiple components on one object to create complex behaviors.

Unity provides Rigidbody, Collider, Light, Camera, and many more out of the box.

Write your own C# scripts and attach them as components for unique gameplay logic.

Introduction

to Physics

Unity's physics engine simulates the real world using forces, gravity, and collisions. By adding physics components to GameObjects, your objects gain realistic behavior. They fall, bounce, slide, and respond to impacts just like objects in the physical world.

Colliders: How Objects Know They Touch

A Collider is an invisible shape attached to a GameObject that defines its physical boundary. When two Colliders overlap, Unity detects a collision and can trigger responses like bouncing, stopping, or running a script. Common types include Box, Sphere, and Mesh Colliders. Choose based on your object's shape for accurate and efficient physics interactions.

Rigidbody

The Rigidbody component brings physics to life in Unity. By adding a Rigidbody to a GameObject, you enable gravity, mass, and force interactions. Objects fall, collide, and respond to pushes just like in the real world, making your game feel dynamic and immersive.

First Look

at Scripts

Scripts in Unity are components, they attach to GameObjects just like any other component. Written in C#, scripts define custom behaviors: moving objects, detecting input, triggering events, and more. Think of a script as a set of instructions your GameObject follows every frame.

Physics Playground Mini Project

Put your skills to the test! Build a small physics-based scene in Unity using GameObjects, Rigidbodies, and Colliders. Experiment with gravity, mass, and forces to create a dynamic, interactive playground that reacts to the real world.