text: // External components
  import React from 'react';
  import { Header, List } from 'semantic-ui-react';
  import { Link } from 'gatsby';
  
  // Internal components
  import Layout from '../../components/Layout';
  import SEO from '../../components/SEO';
  import Navigation from '../../components/Navigation';
  import { JDH1, JDH2 } from '../../components/JDH1H2';
  
  // Helper functions, styles, images, etc.
  import styles from '../../styles/styles.module.css';
  
  const Concepts = () => (
    <Layout>
      <SEO
        title={'Concepts'}
        description={'A link to all of the Johnny.Decimal concepts pages.'}
      />
  
      <JDH1>Concepts</JDH1>
  
      <p>
        In this section I will walk you through all of the core concepts in
        detail.
      </p>
  
      <p>
        I <strong>strongly</strong> recommend that you read the core concepts
        section end-to-end, in the order shown below, at least once. This will
        give you a solid grasp of the system; you may then choose to use
        individual sections like a reference manual.
      </p>
  
      <p>
        As you read it, you’ll have questions. Hold your horses and keep reading –
        I believe I have addressed most of them, but because this is a linear
        thing it might take me a few pages to get there.
      </p>
  
      <p>
        The basic idea of Johnny.Decimal is very simple, but its power comes when
        you truly understand it. Reading this should give you that understanding;
        if you still have questions, or if I have not made something clear, please{' '}
        <Link to="/contact/">get in touch</Link> and I will help you.
      </p>
  
      <JDH2>Core</JDH2>
  
      <p>
        You should be familiar with this section before you attempt to start your
        own Johnny.Decimal system.
      </p>
  
      <List bulleted>
        <List.Item>
          <Link to="/concepts/areas-categories/">Areas & categories</Link>
        </List.Item>
        <List.Item>
          <Link to="/concepts/ids/">IDs</Link>
        </List.Item>
        <List.Item>
          <Link to="/concepts/saving-files/">Saving files</Link>
        </List.Item>
        <List.Item>
          <Link to="/concepts/keeping-notes/">Keeping notes</Link>
        </List.Item>
        <List.Item>
          <Link to="/concepts/tracking-your-numbers/">Tracking your numbers</Link>
        </List.Item>
        <List.Item>
          <Link to="/concepts/developing-your-own-system/">
            Developing your own system
          </Link>
        </List.Item>
      </List>
  
      <JDH2>Advanced</JDH2>
  
      <p>
        You do not need to know everything in this section initially, but you will
        find it useful as you become more familiar with the system.
      </p>
  
      <List bulleted>
        <List.Item>
          <Link to="/concepts/managing-email/">Managing email</Link>
        </List.Item>
        <List.Item>
          <Link to="/concepts/what-about-00-09/">What about 00-09?</Link>
        </List.Item>
        <List.Item>
          <Link to="/concepts/working-at-the-terminal/">
            Working at the terminal
          </Link>
        </List.Item>
        <List.Item>
          <Link to="/concepts/exceptions-to-the-rules/">
            Exceptions to the rules
          </Link>
        </List.Item>
      </List>
  
      <Navigation
        backURL={null}
        backTitle={null}
        forwardURL={'/concepts/areas-categories'}
        forwardTitle={'Areas & categories'}
      />
    </Layout>
  );
  
  export default Concepts;
  