"A template gives you a quick start towards creating a document, spreadsheet, or presentation. Each template has boilerplate content and preset design styles that are meant to be reused. (...) You can then edit the document, replacing boilerplate text and images with your own," explains Google.
The option to use a template is available in Google Docs when you click on New > From template and the list of templates that you've recently used can be found here.
While Google doesn't explicitly offer an option to create your own templates, you can save them as regular documents and use File > Save as new copy (Copy spreadsheet) to create duplicates. If you publish a spreadsheet, append &newcopy to the URL to obtain a template link.
