What is Amateur Radio? Simply put it is a multifaceted and easy to learn communication hobby. It is extremely diverse and is shared by approximately three million people worldwide. It is radio transmission communication shared by amateurs by voice, digital, Morse-code, picture and video. Equipment is no longer bulky and has been replaced by up-to-date latest technology and is very accessible for people of all abilities.
Here is a good starting point for you to investigate further.
...and remember...have a fabulous retirementLIFE!