This is a Gateway netbook, which only holds one stick of RAM. To upgrade, you will have to remove the pre-installed 1 GB stick and install a new 2 GB stick. Gateway has step by step directions on their website: http://support.gateway.com/s/notebook/2009/gateway/lt/lt21/LT21faq6.shtml
We are considering this netbook, and the 2 GB RAM stick would be less than $50 from NewEgg. Hope this helps.