graphic language is introverted and Western is extroverted. These differences are due to the effect of respective traditional and contemporary culture. In the background of internationalization, the communication of Chinese and Western graphic designers become more frequent, they are influencing and changing each other. As regards graphic designers of today, they should not pursue Internationalism blindly or show seeming Nationality on purpose. After all, poster graphic language is for spreading message to the public, no matter it is Chinese& nbsp;or Western. Designers should focus on their target group and create effective graphic language for communicating with them. This is the most important job in poster design.

Conclusions

According to the results of comparison,　analysis and investigation, the effective graphic language for communication has five characteristics:
1. Powerful Function of Communication
Graphic　language should has good ability to attract public attention as soon as possible by its colours,　words,　layout or images.　It was determined by function of poster. In other word, it should be noticeable.
2. Pertinency
Poster must aim at its target group to convey message. Different people have different understanding about same picture.　Designer must think about the factors of age, region, religion and custom. It is necessary to arrange appropriate graphic language to cater for different people.
3. Exact Expression
Designers must sure that their graphic language can express exactly the subject of　poster and not be misunderstand. So, poster graphic language should be typical, reasonable and meaningful. It can appeal to the emotional side of the audience and impress on them.
4. Originality
Innovation is the spirit of design. Good　poster graphic language is unique, and always make audience see something in a way they do not normally see it.
5. Unification of Nationality and Internationalism
Nationality and Internationalism are not incompatible in posters. They usually exist together in a good poster. In other word, good poster is a cross-cultural poster, it keeps its native art charm at the same time of achieving internationalism for the goal of communication. It is very important to modern poster, no matter for its aesthetics or function.