In Plain English
The H1 is the highest heading level in HTML and usually names the visible page topic. It is distinct from the title tag that labels the browser document and may appear in search results.
Why it matters
One clear page-level H1 is generally easiest for readers and teams to understand and manage. H2 and H3 headings can then organise sections and subsections.
Example
<h1>Beginner snake plant care</h1>Common misunderstanding
Modern HTML technically supports multiple H1 elements. That does not mean every large piece of text should be an H1; a single clear primary heading is usually the more manageable convention.