Microsoft Word is perhaps the world's most popular word-processing program, and has been a staple in homes, schools, and offices for decades. Muhammed Selim Korkutata/Anadolu Agency via Getty Images ...

You don’t have to have a word-processing program like Microsoft Word to create postcards at home. Check out these alternatives that let you create postcards on your computer, tablet or smartphone.

Then he has a DOS machine running WordStar, which was the top of the word-processing world when it debuted back in 1983. On his show, O'Brien asked his guest why he still uses the 31-year-old program.