[dba-Tech] What is this?

Microsoft MSDN 2005 Express Edition - ENU

This is showing up in Add or Remove Programs and it's absolutley huge -- as 
big as Office and SQL Server Express.

When I click support it takes me to an only .NET Framework support site. 
MSDN is documentation, support, software downloads -- this isn't something I 
need installed on my local system is it? I don't recall downloading it, so 
I'm a little hesitate to uninstall it, but it's huge -- would love to get 
rid of it.

Susan H.