Graphics Specification

Graphics specification is a list of things you need to consider when designing graphics/a game for a client. This is also known as a brief.

Client Needs - You need to make sure you are following the brief the client has given you, and you need to include what they have asked for.

Audience - The image or game needs to be appropriate for it's intended audience. For example if you're making a game for children you need to make sure there isn't any violence etc.

Thumbnail Sketching - Thumbnail sketching is when you draw lots of different designs of the same thing on the same page, so you can find one that you like. It's basically just putting all of your ideas on to paper and choosing the best one.


Visual Style
Visual style is the way a game looks. Below are some examples of different visual styles in video games. 

An example of a photo-realistic game is GTA V.
 

GTA V is a good example of a photo-realistic game because the game is based on real life locations and the characters are based on real life actors. 

An example of a cel-shaded game is Borderlands.

Despite being quite a gory and violet game, the Borderlands games all have a very silly cartoony/comic book look, which adds to the games humor and makes the franchise very unique, because there’s humor mixed with bloody violence.

Composition

There are different types of image composition, one of them being the rule of thirds. The rule of thirds is when an artist or photographer splits an image into a grid of 9 squares (3x3.) Important parts of the image that the artist wants the viewer to focus on are placed on or near the points where the lines meet up. Leading lines are also used that lead the viewers eyes to the main focus of the image.

Here is an example of an image that uses the rule of thirds. As you can see the building on the right is on top of 2 points. The wires and the ladder connected to the building are leading lines. There are also some leading lines on the floor but not many.

Typography
Typography is the technique of arranging letters and words to make then visually appealing. Typography involves changing things like font size, font colour and the gaps between words etc.

An example of typography. Words have been put together to make the shape of a revolver. Some of the words relate to certain parts of the gun, for example the handle uses the word "hand" and the chamber uses words such as "shoot" and "bang."

Technical Considerations
When developing a game or creating files, you need to remember all the technical stuff. With files you need to make sure you use the correct format, and you need to make sure the size of the file isn't too big (you can use compression to lower file size.) You also need to make sure you give each image/asset the correct filename, and the important assets need to be stored somewhere safe so they won't be lost. With a game you need to make sure it is optimized correctly, because if it isn't it won't run well on certain systems and could potentially be unplayable.