Div tag

In HTML, span and div elements are used to define parts of a document so that they are identifiable when a unique classification is necessary. While other HTML elements such as p (paragraph), em (emphasis) and so on accurately represent the semantics of the content, the use of span and div leads to better accessibility for readers and easier maintainability for authors. Where no existing HTML element is applicable, span and div can represent parts of a document so that HTML attributes such as class, id, lang, or dir can be applied.

span represents an inline portion of a document, for example words within a sentence. div represents a block-level portion of a document such as a few paragraphs, or an image with its caption. Neither element has any meaning in itself but they allow semantic attributes (e.g. lang="en-US"), CSS styling (e.g., color and typography), or client-side scripting (e.g., animation, hiding, and augmentation) to be applied.

The span element was introduced to HTML in the internationalization working group's second draft html-i18n in 1995. However, it was not until HTML 4.01 that it became part of the HTML language, appearing in the HTML 4 W3C Working Draft in 1997.

There are multiple differences between div and span. The most notable difference is how the elements are displayed. In standard HTML, a div is a block-level element whereas a span is an inline element. The div block visually isolates a section of a document on the page, and may contain other block-level components. The span element contains a piece of information inline with the surrounding content, and may only contain other inline-level components. In practice, the default display of the elements can be changed by the use of Cascading Style Sheets (CSS), although the permitted contents of each element may not be changed. For example, regardless of CSS, a span element may not contain block-level children.

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