What is the Right Way of using plugins in PostCSS configuration file?

Question

How do we import plugins in PostCSS? Most of the articles I found online is using the following syntax:

module.exports = {
   plugins: [
     require('<plugin_1>'),
     require('<plugin_2>')
  ]
}

But, in some articles like in Tailwind 3 setup guide, the syntax they uses is something like this:

module.exports = {
  plugins: {
    <plugin_1>: {},
    <plugin_2>: {},
  }
}

So, as a beginner, I'm confused! Which one should I use? Moreover, if you have any articles explaining how PostCSS is configured, Can you share the link with me!