A span is a selection of text that you format as a unit. You can assign a custom style or other formats to the characters included in a span to differentiate that text from the rest of the paragraph. For example, if you want your company’s name to always appear in bold italic, you can create a custom style specifying those attributes. Then you select each instance of the company name as a span and apply the custom style.
You can achieve the same result by selecting the text and manually formatting it from the Properties panel, but when you use a span you can apply a custom style quickly and then change it globally if necessary.
To create a span:
In Page view, select the text you want to format.
Click the Span tool on the Standard toolbox.
The New Span dialog appears.
Select a custom style from the drop-down list, or click the Format button and apply formatting to the selected text.
Click OK.
To remove a span, position the insertion point in the span, click the Span tab on the Text Properties panel, and click Remove Span.