The bottom line is that you must know why you are launching any executable file (see list below). There are countless clever phrases used to trick people into clicking an attachment that wipes out their hard disks. Have you backed up lately? See double extension and extension.
FILE EXTENSIONS
Executables (potentially dangerous)
Know what you are opening!
.EXE (machine language)
.COM (machine language)
.VB (Visual Basic script)
.VBS (Visual Basic script)
.VBE (Visual Basic script-encoded)
.CMD (batch file - Windows)
.BAT (batch file - DOS/Windows)
.WS (Windows script)
.WSF (Windows script)
.SCR (screen saver)
.SHS (OLE object package)
.PIF (shortcut to DOS file plus code)
.HTA (hypertext application)
.JAR (Java archive)
.JS (JavaScript script)
.JSE (JScript script)
.LNK (shortcut to an executable)
Text (safe)
.TXT
Images (safe)
Following are common image file types.
There are many others (see graphics formats).
.GIF
.JPG
.BMP
.PNG
.AI
.WMF
.TIF
.EPS
.PCX
.DXF
Data (potential problem)
.XLS (Excel) Can contain macros that execute.
.DOC (Word) Can contain macros that execute.
Other Data (safe)
Data are processed, not executed, and are thus
theoretically safe. There are hundreds of data
file types (see extension).
![]() | Reproduced with permission from Computer Desktop Encyclopedia. Copyright (c) 1981-2009 The Computer Language Company Inc. All rights reserved. |
Additional Resources
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