The 3 file extension is used by IBM Embedded ViaVoice. This is speech recognition software for embedded devices. The 3 files contain language-specific script data.
Files with the 3 extension are categorized as miscellaneous. IBM Embedded ViaVoice is the most common program to work with these files. It was created by IBM. More details on the software and 3 files are on IBM’s website.
When you double-click a 3 file, Windows looks at the extension. If Windows does not recognize the 3 extension, you get an error. It means Windows does not have a default program set.
You can view 3 files online without needing special software. This lets you see what is inside without other operations. An online 3 viewer works for this.
3 files are usually from IBM Embedded ViaVoice. They are common in China on Windows 10. Google Chrome is the main browser. IBM made the associated software.
To open a 3 file you need a program that supports the format. Some programs can only open 3 files. Others can convert them to other formats.