Broadly speaking, the classification of periodicals can be divided into informal periodicals and formal periodicals. An informal periodical refers to a periodical that is approved by the administrative department to receive the "internal newspaper approval" as an intra-industry communication (generally limited to intra-industry communication and not publicly issued), but it is also a legal periodical. Generally speaking, formal journals have gone through the process of informal journals.
Official periodicals shall be examined and approved by the Press and Publication Administration and the State Science and Technology Commission within the agreed number and incorporated into the "unified domestic serial number". The application for running a journal is relatively strict, which requires a certain publishing strength. Official periodicals have an independent publishing policy.
Understanding the core journals is of great significance. As far as editors are concerned, they can learn from core journals. As far as readers are concerned, establishing the consciousness of core periodicals can clarify the value orientation and improve their reading level. For example, students majoring in language and literature should first read core journals such as China Language and Literature Review, instead of putting the cart before the horse.
As far as libraries are concerned, core periodicals are of course the first choice for subscription under the limited funds. As far as the scientific research management department is concerned, it can make statistical analysis of the papers published by units or individuals in core journals as an important indicator to measure their academic level. Therefore, people often aim at publishing articles in core journals.