Project management helps you to keep track of what projects you are currently working on. Sales pipeline acts similarly for upcoming opportunities that haven't yet become closed deals. Keep track of all of the opportunities - from the ones you're sure will sign a contract to the ones you're dreaming about.
Automatically add opportunities
Use an embedded form on your website to automatically add opportunities for tracking on your pipeline. After you create a form that collects all of the information you want to gather from prospective clients, click settings and then use the dropdown box "Add submission to pipeline." Select which stage of your pipeline you'd like inquiries to be added to (you can customize these stages in your settings).
Manually add opportunities
You can also add an opportunity manually by clicking pipeline in the left nav and using the blue + in the upper right corner. Add in as much or as little detail as you desire. You can also add this opportunity to a current client or a prospective client by clicking "client/prospect."