2D
two dimensional
2D Rigidbody
Allows for a GameObject to has simulated gravity and physics
2D Object
They are tilemaps are sprites
Tilemap
A gameobject that allows you to quickly create 2D levels using tiles and grid overlay
Tile
A class that allows a sprite to be rendered on a tilemap
Sprite
A 2D graphic object. Sprites are just standard textures.
Layer Mask
A value defining which layers to include or exclude from an operation, such as rendering, collison, or your code
Collision
A collision occurs when the physics engine detects that the colliders of two GameObjects make contact or overlap, when at least one has a Rigidbody component and is in motion.
Parent
An object that contains child objects in a hierarchy. When a GameObject is a Parent of another GameObject, the Child GameObject will move, rotate, and scale exactly as its Parent does. You can think of parenting as being like the relationship between your arms and your body; whenever your body moves, your arms also move along with it
box collider: