Some #WP20 perspective:
PHP – 1995
JavaScript – 1995
Flash – 1996
CSS3 – 1999
Blogger – 1999
PHP Nuke – 2000
Drupal- 2001
Movable Type – 2001
๐ #WordPress – 2003
Flickr – 2004
Squarespace – 2004
Joomla – 2005
Shopify – 2006
jQuery – 2006
HTML5 – 2008
Magento – 2008
Ghost – 2013