These two tags are often used inter-changeably by developers for different reasons, so what are the differences between them? How should they be used to markup web pages? The basic difference between the two is their default behaviour. DIV tags are block-level tags and can be used as containers for other tags. SPAN tags are inline tags and should only contain content. These default behaviours can of course be altered by CSS definitions, but are default in any browser context. As a reference, if you want to align text within these tags use the following CSS attributes; DIV - text-align: left|right|center|justify SPAN - float: left|right DIV tags are also used to define logical divisions of page content. It also allows CSS to be defined for whole sections of HTML. By applying an id to a DIV you can also add controls using JavaScript. A SPAN tag is not intended to container other tags, but rather to allow localised styling. This is especially useful when combined with classes. It has even been suggested that future semantic web models will use such markup to define relevant content. For example by defining a class telephone, when can ensure all telephone numbers are displayed in the same fashion: 44-20-555-4444 SPAN tags have similar properties but should be used to reference inline content and apply style by classes. In summary: use divs for defining sections of a page, and spans to enclose and style text or classes of text.

A tag.will only effect one line of text whereas a

tag.is for a block of text.

If you have a line wrapped in a span tag.and it goes to a second line, it will not carry the attributes applied to it to the second line. Because a div tag.is block level, it can be use similarly to a paragraph or header tag.