As the increasing pressure from environment and resources brought by the rapid economic development, environmentalists are advocating energy saving and environment protection. Consequently, the concept of paperless office came into being and becoming an irreversible trend. PDF is an ideal format for paperless office as it has a variety of features.

With the development of technology, education is not the way it was before. Educators are facing the challenge of finding creative ways to teach. Students have to prepare themselves to the competitive world. Colleges need to work more efficiently, put the energy actually in teaching and doing research.

As we know, PDF format is rich in [...]