I've included my own drawings to aid with the explanations. Hopefully these illustrations will be of some help. Read web page sequentially. Skipping around maybe confusing. Plug-ins are programs which expand the computer's ability to view such images and animations.
Atoms appear as spheres.
Depending on the model, bonds are represented as either fused spheres or by sticks. Please remember that these models are only a simplified representation of reality. The emphasis is placed on spacial relationships i.e. bond angles, orientation, and size. The similarities between models and reality end there. Electrons are many magnitudes smaller than the nucleus.