How do two companies merge?

This past week I worked on my final product. After my mentor had given me my new idea on how I should proceed with my final product, I was so excited that I couldn't wait. I started researching the background of Dr. Pepper and Keurig's merging transaction and just getting a basic understanding of each company. I wanted to know how each company's stock was doing as well as how far along they are in the process. Since the first time I even heard of this transaction was when my mentor introduced it to me, everything was a new concept. The only thing I had known about merging companies and Dr. Pepper was that a few years ago, Snapple and Dr. Pepper had merged together, forming Dr. PepperSnapple. I was actually really confused when the two companies merged because both were really popular at the time, and I thought they were competitors, so why would they merge together?

My mentor replied saying that companies merged in order to share resources and have twice the number of work force. Another thing that my mentor said to keep in mind as I do my final product is the negative aspects of merging two companies. Right now, they have two CEOs, two CFOs, and twice the number of employees. Are they going to keep all of them? Or will they pick and choose? And how will they pick and choose? I have much to work on and I am excited for my next mentor visit where I can discuss more about my project with my mentor!