⑴ Printing form: also known as paper type, it is a document type with paper medium as the carrier and writing or printing as the recording means. It is a low-tech document that is convenient for personal use. People are familiar with it, and it is the most commonly used document carrier.
Advantages: portability, readability, markability, affordability, archiving, ownership, durability, etc.
Disadvantages: low information density, small capacity, huge volume, occupying a lot of storage space, and difficult to preserve for a long time.
⑵ Microform: A document form produced by optical materials and technologies, which has a history of over 100 years. Before the advent of holographic technology, information symbols such as characters and images were generally scaled in equal proportion.
Advantages: small size, high storage density, easy storage and circulation, low price and convenient management.
Disadvantages: Need a special reader, expensive equipment, inconvenient retrieval and reading.
⑶ Audio-visual form: Also known as audio-visual form, it uses the principles and technologies of electricity, magnetism, sound and light to express knowledge and information into sound, image, animation, video and other signals, giving people an intuitive and vivid feeling.
It has irreplaceable expressive force in describing natural phenomena and experimental phenomena, such as celestial nebulae and atomic structure. In language learning, this kind of literature also has its uniqueness.
⑷ Electronic type: through the access and processing of data by computer, the digitization of document information is completed, and electronic documents and various electronic publications are formed, including e-books, electronic newspapers, electronic news, electronic meeting minutes, etc. Machine-readable versions are also various, including magnetic tape version, floppy disk version, CD-ROM version, online version and the latest online version.
Electronic documents not only have the characteristics of high storage density and fast access speed, but also have many functions such as electronic processing, editing, publishing and transmission.