The <caption> element in HTML is used to provide a title or a descriptive caption for a <table>. It is placed immediately after the opening <table> tag and is intended to give context to the data presented within the table. By offering a caption, it helps users understand the purpose or content of the table without having to examine all the rows and columns, improving accessibility and clarity.

Visually, browsers typically render the caption above the table by default, centered horizontally. This placement, however, can be customized using CSS, allowing the caption to appear below, left, or right of the table if desired. Semantically, the <caption> element enhances the structure of the document, providing screen readers and other assistive technologies with a clear description of the table’s content, which is especially valuable for complex or data-heavy tables.

It is important to note that each <table> can have at most one <caption>, and while it is optional, including one is considered best practice for accessibility and usability. The <caption> element can contain text or inline HTML elements like <strong>, <em>, or links to provide additional emphasis or context.