The aim of this guide is to give an overview of searching principles, however it's important to remember that each information source - database, website, search engine - will operate a little differently. Therefore you must always check the help pages or guidance on the resource's own website, to ensure you understand how your search is being carried out. What are the search rules? What functions are available? Are any processes carried out automatically? Being fully informed will help you to avoid errors and to make sure you retrieve the right results.