The excerpt tag can be used to create an excerpt of any content that is enclosed within its opening and closing tags.
Unlike the excerptHTML tag, the excerpt tag strips off all HTML tags (except those specified by its allow parameter) from the excerpt it creates.
The maximum number of words that the excerpt can contain. The default value is 50 words.
The HTML elements you wish to preserve in the excerpt.
If you wish to preserve multiple tags, separate the tagnames by using comma e.g.
allow='i, b'
By default the produced excerpt is appended with '...' (three ellipses). You can change this by using this parameter.
This tag does not set any variables of its own.