Deployment
- Before deployment there is something called collections which can be defined in `_config.yml` in root of site so there is site.data, site.posts which are predefined so for more like site.authors type following in `_config.yml`
```yml
collections:
  authors:
    output: true
```
By default it wont output to page so using this when clicked on author it will redirect to its page
More refer to https://jekyllrb.com/docs/step-by-step/09-collections/
- Now going back to root of project so type `cd ..`. as jekyll is installed and all the versions are locked so in order to serve or build with those versions instead of system ones use `bundle exec jekyll serve` instead of `jekyll serve`. this will restrict the enviroment to use gems set in Gemfile.
- Some other important plugins
   -  jekyll-sitemap - Creates a sitemap file to help search engines index content
    - jekyll-feed - Creates an RSS feed for your posts
    - jekyll-seo-tag - Adds meta tags to help with SEO
- in Gemfile
```
source 'https://rubygems.org'

gem "jekyll"

group :jekyll_plugins do
  gem "jekyll-sitemap"
  gem "jekyll-feed"
  gem "jekyll-seo-tag"
end
```
- in `_config.yml`
```yml
plugins:
  - jekyll-feed
  - jekyll-sitemap
  - jekyll-seo-tag
```
now install by `bundle update`
in `_layouts/default.html`
add these tags
```html
<!doctype html>
<html>
  <head>
    <meta charset="utf-8">
    <title>{{ page.title }}</title>
    <link rel="stylesheet" href="/assets/css/styles.css">
    {% feed_meta %}
    {% seo %}
  </head>
  <body>
    {% include navigation.html %}
    {{ content }}
  </body>
</html>
```