Once a book is converted to a digital format, it can be read either on a Kindle Reader tablet or on any other computer or laptop:
How to read Kindle books on a PC using the Kindle PC app
Sign into your Amazon account and visit the Kindle app page.
Click on "Download for PC & Mac" and your download will automatically begin.
Install the software as you would any program file, then open the Kindle for PC app when successfully installed.