DIV tag
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Define a part of an HTML document. This label is often used to set multiple elements into a group and set style for them.
IFRAME tag
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Defines an Embedded Box that contains other HTML documents.
Select tag
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The Select tag is used to create the drop-drop list. The option tag represents the items that can be selected in the list.
Span tag
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The span tag allows you to group inline elements in a document.
The span tag does not change the appearance of the displayed content.
The span tag provides a way to associate a part of text or a part of the associated document. After Association, you can add appearances for them or use javascript to manipulate the content.
References
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HTML <div> Tag
Http://www.w3schools.com/tags/tag_div.asp
HTML <iframe> Tag
Http://www.w3schools.com/tags/tag_iframe.asp
HTML <select> Tag
Http://www.w3schools.com/tags/tag_select.asp
HTML <span> Tag
Http://www.w3schools.com/TAGS/tag_span.asp