A file name extension "associates" that file to the program or type of program that created it. For examples:
A file name is what a file is called. A file extension defines what type of file it is. (Text file, HTML file, executable, etc.)
The main project file has a VBPROJ extension. This is also a file with the same name as the main project file, but with an SLN extension. The SLN extension is a solution file.
. (Dot)
It is a batch command file.
For most typical Word documents the extension is .docFor Excel workbooks (spreadsheets) the extension is .xlsIn general the file extension is the 3 letter/number "code" after the period in the complete file name that gives a hint as to what type of file it is. For example, in the file name resume.docthe word resume is the file's actual name and the .doc tells you that it is a document file.
File extension.
Folders have no extension.
The filename and extension of the file you want to start and .msc (eventvwr.msc)
File extension.
A compatible file is a file name extension (or format) that a program can read.
It is a batch command file.
The extension. It tells Windows what kind of a file it is. For example, a file with the ".doc" extension is a Microsoft Word Document.