.vbs = VBScript
.sql = Transact SQL script
These just happen to be file-types that I work on daily; the file extension is kind of arbitrary however. With an "all files" option you could click on "File" then "Load File" and see more than just files with the extensions of .txt, .suo, or .euo. Therefore I could choose to view "all files" and open anything I want (such as .vbs or .sql files). Many Windows-based programs do this by default, it is handy.
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