A file is a data medium and the data recorded on it.
It is permanent and can be read by people or machines. Examples in software engineering include project plans, specifications, test plans and user manuals.
Documents are important materials for software development, use and maintenance.
A software document or source code document refers to a text entity associated with a software system and its software engineering process.
The types of documents include software requirements documents, design documents, test documents, user manuals, etc. Requirements documents, design documents and test documents are generally written by developers during software development, while non-process documents such as user manuals are written by specialized non-technical writers.
Documents can improve the efficiency of software development, ensure the quality of software, and play a guiding, helping and confusing role in the use of software, especially in maintenance work, documents are indispensable materials.
Early software documentation mainly referred to the user manual. According to Barker's definition, documents are used to record the design, planning and implementation process of software system interface elements to enhance the usability of the system.
Forward, on the other hand, thinks that software documentation is a way of communication between software engineers, and the information exchanged is mainly about the developed software system. On the other hand, Parnas emphasizes the authority of the document, which he thinks should provide an accurate description of the software system.