Adobe Premiere Pro has a vast range of transitions, in this article I will demonstrate what are Premiere pro transitions and what they do by showing preview of the Premiere transitions and  show how to apply them to your footage.

What are Premiere Pro Transitions?
My quick definition is that Premiere Pro transitions presets help you to connect two pieces and multiple of footage, images and audio clips in order to have smooth and seamless effects between them.
Hopefully the Premiere Pro transitions presets preview animations below will speak for themselves. Just click on each tab below to preview all of them.

Premiere Pro Transitions
cube-spin-premiere-transition flip-over-premiere-transition
Cube Spin Flip Over
additive-dissolve-premiere-transition cross-dissolve-premiere-transition dip-to-black-premiere-transition
Additive Dissolve Cross Dissolve Dip To Black
dip-to-white-premiere-transition film-dissolve-premiere-transition morph-cut-premiere-transition
Dip To White Film Dissolve Morph Cut
Non-additive Dissolve
iris-box-premiere-transition iris-cross-premiere-transition iris-diamond-premiere-transition
Iris Box Iris Cross Iris Diamond
Iris Round
pagepeel page-turn
Page Peel Page Turn
band-slide-premiere-transition center-split-premiere-transition push-premiere-transition
Band Slide Center Split Push
slide-premiere-transition split-premiere-transition
Slide Split
band-wipe barn-doors checker-wipe
Band Wipe Barn Door Checker Wipe
 checkerboard  clock-wipe gradient-wipe
CheckerBoard Clock wipe Gradient Wipe