The basic difference between Windows SharePoint Services and SharePoint Portal Server is that the former is primarily based on collaboration theme, whereas the later is based on an aggregation theme and performs the role of a content aggregator. Moreover, Windows SharePoint Services provides "a place to put all your content while SharePoint Server provides an efficient means to navigate and search through your content when you need it." According to Microsoft, "WSS is based on a collaboration theme in the sense that it's designed to store and share list-based data and documents. SPS, on the other hand, is based on an aggregation theme. An SPS portal site is useful for aggregating information and documents from many different places. SPS adds value because it provides users with a quick and easy way to find information and documents that are spread out around a private network or scattered throughout the Internet."