In the course of improving the user interface's capabilities, introduction of speech-controlled systems is only a logical step. It is much more convenient to provide a way to speak to the computer or at least to pose questions in natural language to the machine (which is equivalent in the scope of our study) than applying any kind of programming language to get information about stored data,. Therefore, we need a system that can extract the user's wishes from the linear string that is given and subsequently give answers to the questions.
Again, we face the restriction that also applied to translation: restricted domain of the text in scrutiny. But, sticking to this rule, we can achieve somewhat satisfying results.
All of these examples have a limited range of vocabulary and grammar, which render it slightly impractical for the user to benefit from the system as it may always fall short from understanding certain constructs of the query.
This is a basic problem of all contemporary language processors. Besides, sometimes it is highly impractical to communicate one's wishes by language. When you need to specify certain options it may be faster to use graphic interfaces, and speech recognition interfaces are also inappropriate when it comes to entering confidential data like passwords; too easily one could overhear the input and abuse the gained information. Hence, secure transmission channels must be maintained in spite of more natural (and sophisticated) means of access.

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