The Properties of an object in Roblox describe how that object looks and behaves. For example, a Part has properties such as Position, Material, and Size which determine where the Part is and how it appears. All of the properties of an object can be viewed in the Properties window. After clicking a part, the Properties window will show all of the information about that part. Here you can view and edit the properties of an object. In fact, any changes you make with a tool, such as the tools described in Creating a new game can be made by manipulating the values inside the Properties window.
To open the Properties window, click on the View tab and then click the Properties button.