Zotero [zoh-TAIR-oh] is a free, easy-to-use tool to help you collect, organize, cite, and share your research sources. Zotero is a reference manager. It is designed to store, manage, and cite bibliographic references, such as books and articles. Zotero is a powerful tool for collecting and organizing research information and sources.
Zotero has excellent online documentation.
If you want more details and videos, check out their online documentation including the Quick Start Guide below.