Today's post.
While pagination allows you to iterate over a data set to create multiple templates, a collection allows you to group content in interesting ways. A piece of content can be a part of multiple collections, if you assign the same string value to the tags key in the front matter.
Take care to note that tags have a singular purpose in Eleventy: to construct collections of content. Some blogging platforms use Tags to refer to a hierarchy of labels for the content (e.g. a tag cloud).