Viewports are how you view a 3d scene in a program such as UE4 or 3ds Max. The two main modes of viewing a scene are ‘Perspective’ in which everything looks like it does in to the real world, with depth and objects being smaller when they’re further away etc. ‘Orthographic’ however keeps everything in proportion.
Orthographic is much better if you want precision.
Orthographic is best used when viewing a scene from the side, front, or top. This gives you maximum precision when editing a model.
Modelling in 3d would be almost useless without being able to navigate your scene.
Here is a brief overview of the terminology of basic navigation:
Orbit – Rotating the camera around a point.
Pan – Dragging the camera horizontally/vertically.
Truck – Moving the camera in and out.
There are different ways of viewing your orthographic/perspective viewport. For example, Wireframe Mode lets you see the edges and vertices of your model without any faces (Pictured above in the orthographic viewports).
Next up is ‘Bounding box’ – This is a box that encloses the maximum dimensions of an object.
Colour – This shows the diffuse of your object without any lighting.
Realistic – Lighting, textures etc. Contains full shadows to give a better idea of how your object will look in-game or predict how it may look rendered.