While you can use folders to group your notes, tags are more powerful as a note can have unlimited tags and they don't affect Wikilinks. All your tags are automatically listed in the sidebar and there is a separate tags page that lists all your tags and notes. In addition, the Search support filtering by tags and you can customize the Sidebar based on tags.
Adding tags
Use Frontmatter to add tags to your notes. For a single tag you can directly add the tag name:
---
tags: example
---
My noteFor multiple tags, you can either use a list or the [] syntax:
---
tags:
- one
- two
- three
---
My note---
tags: [one, two, three]
---
My noteTags can include white spaces, but it's not really recommended.
---
tags: ["some tag"]
---
My note