The file formats, or file types are very coherent terms in today's world of computer science.
File Type = Application Assignment (Software, Programs, App)
File Formats = How to interpret the file
The file formats
The file format describes how the file should be interpreted so that the information stored therein can be visually or acoustically displayed or reproduced.
The file type or file extensions
The file type is used to better recognize a specific group of files, such as JPG, JPEG, BMP, .... are image files and TXT, RTF, DOC, PDF, ... are documents. Today's operating systems use the file extensions (file type) to assign the program to which a file type should be opened. The file format is then read and interpreted by the respective applications.
What can I imagine under cross-platform program is a legitimate question, and there is also a simple answer If a program or application is cross-platform,
A function stands for the way of working or the purpose. Often it is called activity and serves a specific purpose The concept of the functions is to perform