Pure Piano
The clear sound of a pure piano, without frills and gimmicks brightens my day. It’s nice that this still exists in today’s world full of shrill colors and sounds.
SQL
The missing part, if you use databases on the server. SQL is the powerful element of dataqueries.
Javascript
This is the conterpart to PHP, while PHP is running on the server, Javascript is used and often needed on the client.
Java is also an island
But in this case not: Java is very important and often used in webpages, but also in other applets and mobiles.