The sandbox refers to the term associated with the secondary index of Google. This is the location of pages that Google deems should not be part of the main index for varied reasons. This means that a page will not appear in regular searches, making it more difficult to gain traffic.
Sean Si is a Filipino motivational speaker and a Leadership Speaker in the Philippines. He is the head honcho and editor-in-chief of SEO Hacker. He does SEO Services for companies in the Philippines and Abroad. Connect with him at Facebook, LinkedIn or Twitter. Check out his new project, Aquascape Philippines