Unity3d is a Game creating software that has both a free and pro version. Because I only have the free version, it will be what i will wrote this essay about. To start, I will discuss gameobjects. A gameobject is any object that exists within the Unity scene. Game-objects, can have many attributes, such as scripts, meshes, colliders, joints, etc.
Components are attached to game objects, Some components follow. A script is one of the most important parts of any game. They allow for control of game-objects, their behavior, etc. Meshes are the shape of a gameobject. They are a very important part of 3d graphics. They are made of polygons, mostly triangles in Unity. Colliders are what allow 3d game-objects to collide with each-other. There multiple types of colliders, wheel colliders, box colliders, sphere colliders, mesh colliders which go directly on the mesh, and more. Joints are like hinges. They can be used to attach game-objects to each other in a hinge or joint like manner. Rigid-bodies are what allow game-objects to interact with the enviorment. With a rigid body, objects can have physics, gravity, mass, drag etc.
The hirachy window is where all of your game-objects are organized. It is also where you can create new game-objects like cubes, spheres, terrain, etc. To add a game-object, right click in the hirachy and click and select your object of choice. Then, use the red, green and blue arrows to position it to your liking. The inspector can be used to edit values, position game-objects, and list and add components.
Terrain is a mostly the ground. It can be molded into almost any shape. It can also be painted to have different textures in different places. Technichly terrain is just a game-object with the terrain compnent. To add terrain go into the hirachy, right click, and click terrain. There are 3 tools for editing terrain, raise hieght, paint hight, smooth, paint, fooliage and trees. The hight brush will raise height when you click the terrain. Paint brush height allows you to set a maximum height. The smooth height allows you to make the terrain more smooth. The paint brush allows you to select a texture and paint the terrain with the texture of your choice. The grass tool allows you to add fooliage of your choice. Trees work much the same as the fooliage.
Assets are custom created objects used in your project. There is an asset store in Unity where you can buy, or download free assets. Assets can be managed in the project folder. An asset is an object stored such as a mesh, or a group of components to create one big object. They can be dragged into the scene to be added to the hirachy.
The scene is an asset that contains data about a world in unity. Each scene will have its own hirachy. Scenes can also be found in the projects tab. The scene view is where you can veiw your cuurent game-objects in that scene. They can also be used to position things.