In this section I will briefly discuss serrations to help you choose a knife that is to your preference.
Some of the knives in the market today give you the option of purchasing it in plain edge (no serrations), fully serrated, and a combo edge (plain edge with some serrations). Serrations have little teeth that are there to help your knife edge get a better grip on the target. I've heard one woman say that her self-defense instructor told her not to get a serrated knife because it can get your knife caught in the bad guy's clothing and make you lose the knife. While I do think this is possible, I also think that is low percentage. For self-defense I personally think serrated knives are the way to go, they can cut more types of material easier than a plain edge, and they stay sharper longer. Generally speaking a combo edge is maximized for multi-task work, such as wilderness survival or general utility. The only reason why I would choose a plain edge over serrations is when I plan to take care of the blade edge on a regular basis for long term maintenance. Please keep in mind that serrations are harder to sharpen than a plain edge.
~Discussing Blade Shapes~
Now let me go over some very basic blade shapes. Let me begin with the Tanto. The Tanto has a very strong tip that can stab through some tough material. It is not a smooth stabber, but you don't have to worry about the tip breaking off compared to other blade shapes. The straight edge is also easy to handle, and makes straight clean cuts. A dagger is double edged, often times illegal, and very good for stabbing, but the double edge makes it more dangerous for anyone around it, including the user. Any type of blade where the spine is angled down is either called a drop point or a clip point. These blades make stabbing easier than a Tanto but the tip becomes weaker. These blades also feature a curved edge with some belly, making them versatile knives, a prime example would be something like a Bowie knife that is used for wilderness survival and combat. A Wharncliffe blade has a straight edge but the spine curves all the way down to the edge, just think of an exacto knife but the edge is on the other side. This kind of design blends the tip with the edge which can be good for precision cutting and changing angles. The Hawk's Bill Blade is a curved blade that makes the tip easier to catch on a target, the curved blade also allows you to maximize edge to surface area on a target so you can tear that area out. Persian blades are upswept curved blades that have a big belly. A belly allows for a deeper cut and the curved blade allows for a deeper hooking-in stab.
My opinion is that one isn't better than the other, it's really a matter of preference and what your intending to do. For example if you think in a real life situation that your just going to go berserk and stab a person as hard as you can anywhere regardless of what they are wearing then a Tanto is probably your best bet and it makes no sense to carry a curved blade.