There are three major types of zombie film; each one was once popular but in general gave way to more exciting and epic genres of zombie. In order:
Necromancer zombie films: A necromancer raises up some bodies for his own purposes, giving them a semblance of life, one by one. Only a few modern zombie films follow this "voodoo" stereotype, and include the Reanimator films. See: Necromancers and Zombiefication: Toxins and Voodoo.
Apocalyptic/epic zombie films: Since George Romero's Night of the Living Dead (1968) a new form of zombie film created a new genre of film. The recently deceased started re-animating and attacking the living. The zombies are slow and suffer from rigor mortis, and move awkwardly and slowly. Their strength is solely in numbers, plus an uncanny ability to tear apart the bodies of the living with their hands and teeth. The phenomenon tends to spread and become more serious over time, often causing the collapse of civilisation and threatening all of humanity to extinction.
Fast and aggressive zombie films: 28 Days Later (2002) saw a new breed of zombie arise which is fast, aggressive and strong. These films have proven more popular and more exciting than any of their introspective predecessors, World War Z (2013) being particularly successful.
For more, see:
Cause of Zombies:
Virus from Science Lab
A modern zombie film, breaking with the traditional depiction of zombies. In this film, a disease spreads throughout the UK... we see riot-like scenes of the zombies fighting police. The infection causes an almost immediate change: people don't have to die before turning. This means that the monsters are not actually zombies. But despite that technicality, 28 Days Later is definitely a zombie film. The undead are strong and fast, aggressive and alert... and this makes for much more realistic violence and fear throughout the film. With this film, zombies are once again to be feared, like in Night of the Living Dead when they were a new cinematic concept.
A small group of soldiers and survivors meet up... and then the plot becomes very similar to Dawn and Day of the Dead: Internal problems cause the group to disintegrate. The film ends on an up-beat note as the survivors realize rescue seems imminent, and the zombies are mostly starved to death. 28 Days Later has some genuinely emotional moments. One where the main character is introduced and he finds a "Missing Persons" board in London, covered in hundreds of messages... and sees the newspapers with "EVACUATION" headlines. Another when he finds the bodies of his parents, who killed themselves while he was in a coma, and they've left a message which ends with the instruction "don't wake up".
The Dawn of the Dead (2004) remake by Zack Snyder covers George Romero's Dawn of the Dead. The biggest change is that it is no longer a b-movie. Everything is much fresher, and it has none of the cheapness or b-movie gore of the classics. The remake centres around the shopping mall again. Memorable scenes include the "sniper" scenes where they pick off zombies from the horde outside, and the baby scene was pretty gruesome as they hope in vain that a pregnant woman's baby will be born alive (it isn't). To an extent, this remake contains many of the best elements of the original movies, but in another, it lacks the concentration on personal strife of the originals.
The following is an extract from World War Z (2013) Film Review.
Cause of Zombies:
World War Z covers genuinely new ground as far as zombie films go. Some of the first zombie films were about very local infections; Night of the Living Dead (1968) saw a survivor whole up in a house for a single night, until the cavalry arrived, sweeping the countryside and clearing all the zombies. The same with Shaun of the Dead - the Army arrives in the morning and clears everything up.
Most zombie films since then are about a few survivors in a house, in a mall, or underground, or on the road, in a world where civilisation has already passed away. Even films like 28 Days Later, where the infection only affects just the UK, is post-apocalyptic in that for the whole duration of the film there is no hint of government or of the rest of the world (i.e., in feeling it is post-apocalyptic, although not technically in fact). In Romero's Diary of the Dead and Survival of the Dead we see the infection spread anew, but, the films are away from all the action, down backroads, in woods, on an island... away from civilisation, and away from any military resistance to the plague.
“World War Z... is, truly, the first zombie war film.”
World War Z covers the middle ground - it comes after the initial infection has spread but before civilisation has fallen. This is the awesome, world-changing epoch where governments and organized armies are fighting the undead with all their weapons, intelligence services, and with international flights and airports still partially up and working. It is, truly, the first zombie war film. Little hints of "reports of rabies in 24 countries" (approximate quote) are heard from news reports in the background in the first few minutes of the film.
The strength of the Air Force and the mobility of the Navy are no match for the zombies in cities. Throughout the film we get see cities collapse and fall rapidly from a hugely violent and catastrophic spread of zombies in densely populated areas, and it is depicted perfectly. In 28 Days Later and 28 Weeks Later we see some scenes where in the flood of running bodies the armed guards cannot tell who is infected and who is running for their lives. This films takes that problem up a few notches.
When it comes to fall of cities in World War Z, there is no doubt that that is how it would happen. The opening of the film sees Brad Pitt (playing Gerry Lane, a United Nations investigator) witness the speed at which the aggressive zombies spread through the streets, with emergency services on the verge of reacting but not quite getting their act together. The same happens in Planet Terror in the hospital in the first half an hour - as the medical staff realize the seriousness of the symptoms of all the incoming patients, it is too late to do anything except a little "self preservation". In World War Z, As quickly as the police are being mobilized, the violence has spread over them. There is a sense that no evacuation plan could possibly be quick enough.
Suddenly, bam, the zombies are everywhere, in every country, and dominating every news channel.
From then it seems that most international contacts are lost; the USA's Naval command center, at sea, never receives word from India ('a black hole') and other hugely populated countries. It is Eastern Asia that it appears it started - South Korea, perhaps. Those who have read the book know it started in China although the film cleverly has the cast not quite find this out. The only presumption is that they are completely overrun. Brad Pitt sets off in search of the cause of the epidemic with a short-lived virologist - there is precedent for the fact that if you understand the genetic heritage of a disease, you can understand much of how to stop it. Wherever they go, however, they see humanity in retreat: walls are being overrun, functional airports are becoming few in number, and eventually, they are stranded while en route to a World Health Organisation research centre.
The rest of the film is set in the WHO centre. Pleasingly, many classic zombie-film devices are now in play; there are a few survivors holed up indoors, and they have to use their ingenuity (rather than brute force) to get by. They sneak past zombies, create diversions, and all the while work on their plan on creating a form of vaccine. More about that below. This is the more thrilling part of the film, with much less need for the loud-bangs and war-fighting that, at the end of the day, does not entirely suit zombie films. The aggressive zombies are more docile when non-stimulated, so the trick is to be quiet, move slowly, and be sneaky... throughout the first part of the film, we are often left annoyed that the lead characters can't take this approach more often!
The film winds up here and subsequent snapshots tell us that the WHO vaccine is slowly allowing humankind to fight back more effectively, street-by-street. We see some large-scale destruction of docile zombies and hear commentary that there are still many groups of survivors, each finding different ways to survive - we already saw that, perhaps, North Korea evaded the early epidemic by pulling out the teeth of all of its citizens therefore stopping the rapid spread of the infection due to bites. So the film ends with a clear depiction of how humankind can claw its way back to dominance, via the same type of medical science that probably created the epidemic in the first place. Nonetheless, it is a satisfying film from both an action point of view, and from a thinking point of view, and has a lot in it both for the fans of classic zombie films (with survivors sneaking around), and for fans of aggressive zombie films (with plenty of enraged zombies to properly fight against).