Igbinary is a drop in replacement for the standard PHP serializer. Instead of time and space consuming textual representation, igbinary stores PHP data structures in a compact binary form. Savings are significant when using memcached or similar memory based storages for serialized data.
But where does the name "igbinary" come from? There was once a similar project called fbinary but it has disappeared from the Internet a long time ago. Its architecture wasn't very clean either. IG is an abbreviation for a Finnish social networking site IRC-Galleria