Ghost generates automatic meta data by default, but it can be overridden with custom content in the post settings menu. Meta data is output by default in ghost_head, and can also be used in themes with the following helpers:
{{meta_title}}– the meta title specified for the post or page in the post settings{{meta_description}}– the meta description specified for the post or page in the post settings{{canonical_url}}– the custom canonical URL set for the post