In Tim Gunn's book "Tim Gunn's Fashion Bible" on page 277 it discusses what types of bags you should carry to certain places and events.

For most of us teens, we are usually out for dinner with family or friends, Gunn recommends carrying "smallish leather or metallic bag" (Gunn and Calhoun 277). A small bag is good when you are going out to eat because it can hold all your necessities, which are probably your phone, wallet, and maybe some other items. By having the bag be leather or metallic, it makes your look, fancier, and adds a little pop! When I go out to dinner I like to take my small black leather bag, because it goes with everything and I can fit everything that I need in it.
What type of bag do you most often carry?
Gunn, Tim, and Ada Calhoun.Tim Gunn's Fashion Bible: The Fascinating History of Everything in Your Closet. New York: Gallery, 2012. Print.
When you are going out to a formal event Gunn suggests "Formal event: tiny clutch" (Gunn and Calhoun 277). By wearing a small clutch it is also practical because you shouldn't have to carry so many things with you. When you look at this picture of Chrissy Teigen, you can see that the small clutch not only looks great with her look but is also practical because the most she needs to carry with her is her phone and a couple of other items that are small enough to it in her bag.
When you are going out to attend a business meeting Gunn says that you should carry a leather briefcase or carryall bag, this makes you look more professional which you should aim for since it's a business meeting (Gunn and Calhoun 277). By using a carryall or briefcase it is also practical, because in meetings you may be handing out papers or receiving them, and these bags have enough space for you to carry those papers. Also, they have room for your laptop or electronics that you may need for your meeting.

For most of us teens, we are usually out for dinner with family or friends, Gunn recommends carrying "smallish leather or metallic bag" (Gunn and Calhoun 277). A small bag is good when you are going out to eat because it can hold all your necessities, which are probably your phone, wallet, and maybe some other items. By having the bag be leather or metallic, it makes your look, fancier, and adds a little pop! When I go out to dinner I like to take my small black leather bag, because it goes with everything and I can fit everything that I need in it.
What type of bag do you most often carry?
Gunn, Tim, and Ada Calhoun.Tim Gunn's Fashion Bible: The Fascinating History of Everything in Your Closet. New York: Gallery, 2012. Print.