A symphony is an extended musical composition in Western classical music. At least if you would believe the Wikipedia definition. In my world however, it is a grievous typo for one of the world's most powerful web frameworks — Symfony.
I can see how Wikipedia could make the mistake. It is definitely not uncommon for newcomers to get it wrong after just hearing Symfony pronounced. So let us correct the error.
The reason for spelling with an F dates back to 2005, when Fabien Potencier decided to open source the framework he had been creating within Sensio Labs. Then named Sensio Framework, Fabien wanted something that would fit with the
sf prefixes used throughout the codebase.
In the words of Fabien himself:
The first name was Sensio Framework (Sensio is my company). So, all classes were prefixed with sf... and as a lazy dev, I didn't want to rename my classes with another prefix, so I was looking for a name with a S and a F inside. When doing some brainstorming for a good name, symfony (with a F, not a PH) came up.
The rest is history.
Nowadays we use Symfony2, without the space, when talking about the current version. This helps when looking for posts and discussions on how to solve specific problems, without getting the old versions.