This Mind Map from Credo is a great exploration tool. You can click on topics to open up more ideas in that area. For fullest use, click the View in Credo link at the bottom. You will get the same map and Credo's excellent resources all on one page.
An important resource for those needing to understand the key concepts in philosophy and ethics and their relevance to current issues. It covers a wide range of philosophical ideas including often-neglected non-European traditions such as African philosophies and Islamic ethics.