What's the difference between a language and a metalanguage?
A
language is a single specification - a way of describing a series of actions or how some particular data is handled. Whereas a
metalanguage is a way of specifying a series of languages to a particular pattern.
An example? HTML is a language. There are different flavours (slightly) but basically it's a single language. What I descibe as HTML++ is a metalanguage - a way of adding to HTML to make it rather more that just HTML. Examples of HTML++ metalanguages include JSP, PHP, ASP, Rails, Eruby, EmbPerl, SSI; all differently languages as you need different compilers / interpretters to handle them, but all extending basic HTML in a similar way.
In the same way, XML is a metalanguage, and implementetations of it include XSLT, RSS, and many more from SOAP to Tomcat configuration files.
Update - January 2010 - we have added an optional Ruby on Rails day to our Ruby courses because it is becoming so popular - see
[here] (written 2007-01-22, updated 2010-01-31)
Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articles
R202 - Ruby on Rails [1302] Ruby, Ruby, Ruby. Rails, Rails, Rails. - (2007-08-13)
[1375] Python v Ruby - (2007-10-02)
[1745] Moodle, Drupal, Django (and Rails) - (2008-08-08)
[2605] Ruby on Rails - a sample application to teach you how - (2010-01-30)
[2607] Answers on Ruby on Rails - (2010-01-30)
[2609] Scope of variables - important to Ruby on Rails - (2010-01-31)
[3624] Why do we need a Model, View, Controller architecture? - (2012-02-25)
[3756] Ruby on Rails - how it flows, and where the files go - (2012-06-08)
[3772] Hello World - Ruby on Rails - a checklist of each step - (2012-06-22)
[3777] Multiple views in a single appication - sharing common parts of the template - Ruby on Rails - (2012-06-23)
[3778] Providing a form to allow the user to add data to the model - Ruby on Rails - (2012-06-23)
[3779] Adding validation to form entries and sticky fields - Ruby on Rails - (2012-06-23)
[3780] Ruby of Rails - cleanly displaying model data in the view - (2012-06-23)
[3919] What is a web framework? - (2012-11-10)
[4010] Really Simple Rails - (2013-02-17)
[4013] Web Frameworks - nested templates - (2013-02-22)
J907 - JSP - JavaServer Pages [79] Last day of Java - (2004-10-08)
[1550] Java (JSP and Servlet examples) live on our server - (2008-02-23)
[2147] A very easy JSP (Java Server Page) - (2009-05-01)
[2151] What is a JSP tag library? - (2009-05-01)
[2183] Servlet life cycle, and Java Servlet variable scope - (2009-05-16)
[2525] Using JSPs, Tag Libraries, Java Beans, Tomcat in one short example - (2009-12-04)
[3046] Java Beans, tag libraries and JSPs - what and why. - (2010-11-13)
[3997] Servlet v JSP (Java Server Page). What is the difference? - (2013-02-06)
H101 - Introduction to PHP [48] PHP - onwards and upwards - (2004-09-14)
[55] Evening classes to learn PHP - (2004-09-19)
[93] Case Sensitive? - (2004-10-19)
[124] PHP v Java - (2004-11-20)
[132] Portrait of the author - (2004-11-27)
[135] Too many Perls - (2004-11-30)
[317] Programming languages - a comparison - (2005-05-20)
[341] Happy Birthday, PHP - (2005-06-09)
[380] Bridging to the customer requirement - (2005-07-16)
[382] Central London Courses - Perl, PHP, Python, Tcl, MySQL - (2005-07-18)
[433] FTP - how to make the right transfers - (2005-09-01)
[577] Learning to program in Perl or PHP - (2006-01-26)
[624] It's REALLY easy to add a little PHP - (2006-02-26)
[629] Choosing the right language - (2006-03-01)
[646] PHP - London course, Melksham Course, Evening course - (2006-03-14)
[691] Testing you Perl / PHP / MySQL / Tcl knowledge - (2006-04-19)
[712] Why reinvent the wheel - (2006-05-06)
[789] Hot answers in PHP - (2006-07-02)
[795] Remember a site's non-technical issues too - (2006-07-07)
[846] Is Perl being replaced by PHP and Python? - (2006-08-27)
[917] Syntax checking in PHP - (2006-11-07)
[924] The LAMP Cookbook - Linux, Apache, MySQL, PHP / Perl - (2006-11-13)
[949] Sludge off the mountain, and Python and PHP - (2006-11-27)
[1198] From Web to Web 2 - (2007-05-21)
[1717] Q - Should I use Perl or Python? - (2008-07-23)
[1753] Perl v PHP, choosing the right language - (2008-08-14)
[1958] PHP - Parse error: syntax error, unexpected $end ... - (2008-12-23)
[2097] PHP Course - for hobby / club / charity users. - (2009-03-22)
[3025] Learning to Program ... in PHP. Course examples. - (2010-11-01)
[4118] We not only teach PHP and Python - we teach good PHP and Python Practice! - (2013-06-18)
[4621] The power of scripting - (2016-01-12)
A301 - Web Application Deployment - XML, DTD, XSLT, XHTML and More [653] Easy feed! - (2006-03-21)
[1901] XML, HTML, XHTML and more - (2008-11-23)
[2246] What difference does using the XHTML standard really make? - (2009-06-18)
[2378] Handling XML in Perl - introduction and early examples - (2009-08-27)
[2554] Adding retrospective ALT attributes to IMG - (2009-12-28)
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UK legal requirements for your commercial web siteSorting people by name in PHPLearning to write secure, maintainable PHPToo busy to blog it - but it's great (mostly)The HTML++ MetalanguageJava 6, Apache Tomcat 6.Getting rid of people - hotel techniquesMaintainable code - some positive adviceBounce, bounce, bounceBang! Train campaign hits home