Visual effects have been used in cinema since it's origin, and the term refers to various processes and techniques that are used to manipulate (or completely create) imagery seen in film. Many different methods and technology has been created over the years, with the aim of making visual effects more realistic and awe-inspiring; allowing an audience to further escape into a films world and story.

When talking about the history of visual effects, most people will think of George Melies; whom is seen as the father of special effects. Melies started his career as a film maker in the 1890's and discovered a way to manipulate film imagery in 1896- when his film accidentally jammed and caused a shot to change quickly, making the scene suddenly change. This inspired him to experiment, leading to the creation of many early visual effects techniques. For example, his film La Caverne Maudite (1898), used double exposure- when two images are superimposed together in order to create one manipulated image- to make ghosts and spirits appear in the cavern of demons. Another one of Melies' films (Un Homme de tete- 1898) was also the first to use split screen, which is a technique including filming the same shot twice, and then putting the images together. This allowed an actor to perform alongside himself, and was used for many years after (For example in Disney's The parent trap of 1961). Melies was also known for using stop motion in his films, for example in his adaptation of Cinderella (1899), which was a popular technique used often in early cinema.

From George Melies "A trip to the moon" (1902), which used special effects to create a story of man's first venture into space.

Stop motion is a technique as old as film itself, and was used in most films -that required visual effects- before the development of CGI. Famous examples include King Kong (1933), Jason and the Argonauts (1963) and The empire strikes back (1980). In most cases, it was miniatures that were used for stop motion (which were used in Melies film's also). However miniatures had other uses too- they could create whole cities, such as in Metropolis (1927) and are still used in modern cinema for that reason. The Lord of the Rings trilogy (2001-2003) used miniature towns and buildings alongside computer generated backgrounds in order to create the world of middle earth. Before this, matte paintings were used as backgrounds for many films in order to create a fantasy land.

From "The Wizard of Oz" (1939) an example of a matte painting used as a background.

These techniques are still used in some forms in modern cinema, however, after the dawn of CGI, the world of visual effects began to change dramatically. CGI (or computer generated imagery) was developed alongside the development of computer technology; but it's start in film began with the first fully CGI character in Young Sherlock Holmes (1985). This was created by Lucasfilms visual effects division ILM (Industrial light magic)- which was formed to create the already ground breaking effects in the Star wars films. Even before this CGI creation, the group had already been innovating in the special effects business. For instance, ILM created the Dykstraflex, a motion-controlled camera that is controlled digitally. This allowed for more complex shots and movements that could be recorded and therefore repeated; it was used in Star Wars episode IV: A new hope(1977).

This breakthrough in computer animated imagery encouraged more companies to experiment with this technology, and led to a range of new techniques that improved visual effects' realism and impact. Despite this, old methods where still used alongside the new computer technology. Jurassic Park (1993) used CGI to create some of the film's dinosaurs, however animatronics where used for a majority of them- as the digitally created creatures did not seem realistic enough.

A dinosaur animatronic being built for "Jurassic Park".

Illustration SEQ "Illustration" \*Arabic 1: Andy Serkis in a motion-capture suit whilst filming the "Lord of the Rings".

One technology that could add more realism to computer generated characters is motion capture. This process includes having actors -wearing a special suit covered in sensors- being filmed, and then being accurately recreated digitally using the recorded data. Some forms of this occurred before CGI; such as roto-scoping, which was a technique where actors were filmed, and then drawn over frame by frame- therefore capturing their motion. This occurred as early as Snow White and the seven dwarfs (1937).

Motion capture is used in most films that require a non-human character, and the most popular example is probably Gollum from the Lord of the rings trilogy. Gollum was acted out by Andy Serkis, who was filmed by 13 different cameras, each focusing on certain sensors. This was transferred online into a 3D model, that could then be fleshed out to create the character. The first film to use this method for all it's characters was The Polar Express (2004), which allowed Tom Hanks to play a range of characters. It was directed by Robert Zemeckis, who continued to use the method in his later films Beowulf (2007) and A Christmas Carol (2009).