Complex sentence: In the 1980s or early 1990s a computer without a floppy drive would likely seem unthinkable, however they are becoming more common today, and a program hard coded in that manner 15 years ago could face serious problems if no update were made.
Split into simpler sentences: In the 1980s or early 1990s a computer without a floppy drive would likely seem unthinkable, but they are becoming more common today. A program hard coded in that manner 15 years ago could face serious problems if no update were made.