The document is a tutorial that introduces Invoicely, a free online invoicing tool that allows small businesses to create and send invoices. It guides the user through the process of setting up an Invoicely account, creating an invoice for a client, and sending the invoice via email. This includes adding client details, line items, taxes, links, notes, and integrating payment options like PayPal. The tutorial also explains how to view invoices and payments and customize business settings.