Multipurpose Internet mail extensions Hypertext Markup Language (Mime HTML or MHTML) files are a combination of two common Internet technologies. The most common uses of this format are to save all contents of a webpage to a single file and send multimedia e-mails. More advanced possibilities include, distributing e-books or other types of static content, reducing the number of requests a web browser makes when downloading content from a server, and even recording and transferring images on a computer screen for troubleshooting purposes.
MHTML files are a fusion of two commonly used Internet technologies: HTML, the text markup language used to define the layout and structure of webpages, and MIME, a series of extensions that expanded e-mail beyond simple text messages. Although these technologies were not originally meant to be used together, the HTML model of referencing external content through simple snippets of text coupled with MIME’s ability to encapsulate multiple pieces of content into a single file turned out to be a powerful combination. In 1999, the Internet Engineering Task Force (IETF), an unofficial standards organization, approved MHTML as a proposed standard, thus paving the way for further developments.
If you’ve ever sent or received an e-mail message that included images or was formatted like a webpage, you’ve probably already used the MHTML format. E-mail was the original focus of the format, but it didn’t take long for other uses to be found. Some web browsers now allow saving complete webpages as MHTML files, making the format a quick and easy way to download and archive receipts, news articles, and virtually any other type of web content. This type of web page archive can also be sent to a friend through e-mail or distributed to colleagues over a local network.
For power users, MHTML files present a number of interesting possibilities. MHTML files can distribute multipage documents such as corporate reports, e-books, help files, or manuals and even simple websites. Many word processing, spreadsheet, and presentation programs support exporting documents in MTHML, which can be useful to send the files to someone who may not have the same set of programs installed. If you have a particular problem with your computer that is difficult to describe, a tool known as the Problem Steps Recorder can save step-by-step pictures of your computer screen, complete with your own text commentary, to a single MHTML file that can be sent to a friend or family member for troubleshooting purposes.
Some web developers have started using MHTML files to package graphics, style sheets, and other resources into a single file, which reduces the overhead involved in transferring content from a web server to a web browser. The software that powers most Wiki sites allows users to upload MHTML files, which are then displayed within one of the Wiki’s page. If you're a database administrator working with Microsoft® products, you can configure the SQL Server Reporting Services tool to export reports in MHTML format.