The Webmaster's Lexicon: M

Mailto	An HTML tag used to send E-mail to a specified address. Mailtos are frequently used with forms to transfer the data input from forms an E-mail account.
Markup	Syntactically-delimited characters added to the data of a document to represent its structure. There are four different kinds of markup descriptive markup (tags), references, markup declarations, and processing instructions.
MCF	Meta Content Framework (MCF) is a proposed standard data definition language which is an application of XML. The purpose of MCF is to define a open standard for describing data content which includes a data structure definition format. The data content is information typically found in email headers, web site descriptions and ftp directory structures.
Media Type	Definition of a file type so that an E-mail program, browser or other application can more readily process it. Media types are also called MIME types. The media type "video/mpeg" indicates that a file is an MPEG video. The type "text/html; version=3.0" indicates that a file contains HTML source that relies on HTML 3.0 -- files for HTML 2.0 have a media type of "text/html" without a version number.
MIDI	Musical Instrument Digital Interface. A music definition language and communications protocol enabling electronic instruments to communicate musical information.
MIME	Multipurpose Internet Mail Extension. A description of the contents of a file or attachment, now called Media Type.
Meta	An HTML tag used in the Head area of a document to specify further information about the document, either for the local server, or for a remote browser. The META element is used within the Head element to embed document meta-information not defined by other HTML elements. Such information can be extracted by servers/clients for use in identifying, indexing, and cataloging specialized document meta-information. In addition, HTTP servers can read the contents of the document head to generate response headers corresponding to any elements defining a value for the attribute HTTP-EQUIV. This provides document authors with a mechanism for identifying information that should be included in the response headers of an HTTP request.
Metasearcher	Search engines that simultaneously pass a user's query on to several other search engines in parallel. The term is frequently mis-applied to pages containing several search engine forms that operate independently, i.e. no parallel search is performed.
Method	A way in which HTTP requests may be delivered to a server.
Module	Part of a software program.
Mouseover	An element in JavaScript that triggers a change in a graphic (or other item) on a webpage when the mouse is moved over it. Mouseover's are usually used to create a highlight or button movement on an image that is used as a link to another page.
Multimedia	Means additional to text for conveying information to users, e.g. audio and video.