Brief History

Version 5, current
Rewrote to ASP.NET MVC C# to use online
Version 4, current
This online version is rewrote completely from scratch with ASP.NET Web Form C# to use online; except for the user interface, the features are almost the same as in version 2. As of now, 10/2010, it's still in the "beta test" phase, hopefully will be done soon.
Version 3
It's version 2 with the new interface to use with Windows, finished in late 1995. This version was chosen by Microsoft to include in Microsoft Office 95 Vietnamese Edition. However, the detail agreement did not gone through and it was not released to the public. The program was written in C++, using MFC for Windows.
Version 2
Was released in March, 1993 with new features, operated in DOS environment and used to check document in text format. In this version, besides checking spelling errors (typo), it was able to check incorrect word usage as well. This version could check for more than a dozen different 1-byte Vietnamese character sets like VN Labs, VNI, VISCII, etc.
Version 1
Completed in September, 1990, it was used by a limited Vietnamese newspaper publisher in Southern California. It operated under the DOS environment to check for typo and suggestion the corrections. It was able to check only text file using VNLabs character set. The program was developed using C and Assembly.