Jekyll uses the Liquid templating language to process templates.
Generally in Liquid you output content using two curly braces e.g. {{ variable }} and perform logic statements by surrounding them in a curly brace percentage sign e.g. {% if statement %}. To learn more about Liquid, check out the official Liquid Documentation.
Jekyll provides a number of useful Liquid additions to help you build your site:
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Licensed under the MIT license.
https://jekyllrb.com/docs/liquid/