Hmmmm, it depends on several factors; 1. Where am I going, 2. How am I going to get there, 3. What time of year it is (i.e. type of clothing I'm wearing), 4. What do I plan on doing when I get where I'm going (is shooting on my to do list, if so, what kind).
These are the basics I use in determining what I will carry TODAY, and tomorrow may be different depending on the answers to these questions. Having said that, I like everyone else, have my favorites. One is a S&W 637 Airweight .38+P, and my "go to" CCW gun is a Springfield Armory Ultra Compact 1911 .45ACP. I must admit, I periodically carry a Beretta 92 9mm. My wife also carries, and is very comfortable with any of these.
I have been a Concealed Carry Instructor for many years, and these are the basic factors I use in determining my choice of today. These questions have a myriad of answers, so it's not as easy as it sounds. Perhaps I make things a bit more complicated than they have to be, but my experience has shown "me", those few minutes to reach the proper conclusion could save my life, or yours!!!!! If it's at home, and I'm not, it's worthless if I need it.