There are a lot of styles out there, though, so instead of buying one online, make a point to go into a local retailer and select one that feels comfortable in your hand.
Long serrated knife
Ballpark price: $45
For foods with tough exteriors, like bread, sandwiches, and tomatoes, nothing works better than this sharp-toothed knife. Use delicate, even pressure to cut through food cleanly and without squishing or compromising structural integrity.