Up until the late nineteenth century, second language acquisition was based on an approach called the Grammar Translation Method (See References 2), which is still widely used in some schools although it has largely been replaced by other methods. The Grammar Translation Method was based on the study of dead languages such as Classical Greek and Latin. It emphasized rote memorization of vocabulary lists and rules of grammar, and it tended to produce students with little to no ability to actually communicate in the target language. This wasn't a problem for a dead language such as Latin, but it was not a very effective way to teach a language like French or Spanish that can still be used in daily life. (See References 3) In the late 1800s, educators developed a new approach called the Direct Method. (See References 2)
The Direct Method is based on the idea that the goal of learning a second language is to be able to communicate in that language. The Direct Method takes first language acquisition as its template for second language acquisition. When babies are learning to talk, they doesn't have any other language to help them with the learning process: only the target language is ever used, and the baby picks up grammar, structure and vocabulary by using a language and hearing it used, without reference to grammatical theory. (See References 4)
The Direct Method, when properly applied, can be very effective at creating fluent speakers of the target language who can actually use it to get by in day-to-day situations. (See References 2) The more traditional Grammar Translation Method is often ineffective for this purpose, because it concentrates on giving the student an intellectual understanding of how the target language is structured rather than a direct experiential understanding. (See References 3) Another advantage of the Direct Method is that it mimics the natural experience of acquiring a first language, rather than approaching language acquisition as an artificial exercise. The Direct Method is ideal when presented in a small-class environment. (See References 2)
There are a number of different ways to apply the Direct Method of language acquisition. Vocabulary is usually taught through direct examples---for instance, by picking up a pencil and saying "this is a pencil" in the target language. This has the effect of not only teaching the student the word for "pencil," but also teaching a grammar principle indirectly. This is typical of the Direct Method's inductive approach to teaching the student how the target language works. (See References 4) Teachers may also ask the students questions, have them fill in the blanks in an example sentence, or have them read from a work of literature. All of these techniques emphasize the Direct Method's core strength---teaching students to be able to speak the target language rather than merely be able to translate it. (See References 2)