Structural grammar is an approach to the written and spoken language that focuses on the mechanics and construction of sentences. As such, structural grammar is not concerned so much with the implications of the words used to create the sentence, but with the construct of the sentence itself. This concern with sentence structure provides a basis for the creation of most written documents, and makes an assumption that what is seen on the surface is also the straightforward meaning behind the words of the sentence.
The function of structural grammar can be contrasted with that of transformational grammar. Also known as TG grammar, the transformational approach to grammar looks beneath the surface of the words used in the sentence, and seeks to identify any implied as well as expressed meanings in the arrangement of the words. TG grammar is also usually considered to be the logical progression in comprehension of the written and spoken word, taking the process of analysis one step beyond the boundaries of structural grammar.
While a grammarian may consider the essentials of both transformational and structural grammar to be more complex than these simplified explanations, most would tend to agree that structural grammar provides the framework necessary to convey ideas and thoughts from one person to another. As children, individuals master the basics of sentence construction and learn how to use specific words in a particular fashion. This allows wants and needs to be conveyed efficiently and quickly.