What's the difference between the living zombie and what we call the modern zombie? The modern zombie is the traditional undead, rise-from-the-grave ghoul that is trying to eat you. The newest innovation in zombie culture is what we call the living zombie, and that is the zombie that really got kicked off in 2002 with '28 Days Later', and then even more recently 'Zombieland' in 2009. Those zombies did not die and come back to life; they're just simply just infected with a sickness. Even though in 'Zombieland' it seems as though . . . it's called 'Zombieland', the creatures in the movie are called zombies. They actually don't die and come back to life, they just have contracted an infectious disease that is causing them to turn into raving maniacs who want to run around and try to eat you.
The living zombie has all the same attributes as the undead or modern zombie; it's just that it is not dead. It's relentlessly aggressive human driven by a biological infection. It is infectious, they want to eat you. If they bite you, if you get their blood in you or on you, you'll turn into a zombie, as well. It's just that you don't go though their process of dying and coming back to life. Functionally though, it is essentially the same.
Many zombie purists would say that '28 Days Later' was not a zombie movie because they don't come back from the dead, or even 'Zombieland' is not technically a zombie because they don't come back from the dead. What I would say to that is the experience of watching those movies is very much like watching a zombie movie. They're just as scary. The threat is just as intense. Functionally, they're essentially zombie movies. From a practical point of view, if a raving maniac is trying to claw down my front door to attack, eat me, and turn me into one of it, I'm not really interested in having a debate about whether or not that is really a zombie or is that not really a zombie, because I'm getting my leg chewed off either way.
The end result to you may be the same, but that's the difference between the living zombie and the modern zombie.