A question is an utterance which typically functions as a request for information, which is expected to be provided in the form of an answer. Questions can thus be understood as a kind of illocutionary act in the field of pragmatics or as special kinds of propositions in frameworks of formal semantics such as alternative semantics or inquisitive semantics. Questions are often conflated with interrogatives, which are the grammatical forms typically used to achieve them. Rhetorical questions, for example, are interrogative in form but may not be considered true questions as they aren't expected to be answered. Conversely, non-interrogative grammatical structures may be considered questions as in the case of the imperative sentence "tell me your name".


The principal use of questions is to elicit information from the person being addressed by indicating the information which the speaker desires. However, questions can also be used for a number of other purposes. Questions may be asked for the purpose of testing someone's knowledge, as in a quiz or examination. These are termed display questions. Raising a question may guide the questioner along an avenue of research.
A research question is an interrogative statement that manifests the objective or line of scholarly or scientific inquiry designed to address a specific gap in knowledge. Research questions are expressed in a language that is appropriate for the academic community that has the greatest interest in answers that would address said gap. These interrogative statements serve as launching points for the academic pursuit of new knowledge by directing and delimiting an investigation of a topic, a set of studies, or an entire program of research.
A rhetorical question is asked to make a point, and doesn't expect an answer. As such, it isn't a true question. Similarly, requests for things other than information, as with "Would you pass the salt?" are interrogative in form, but aren't true questions.
Pre-suppositional or loaded questions, such as "Have you stopped beating your wife?" may be used as a joke or to embarrass an audience, because any answer a person could give would imply more information than he was willing to affirm.
Questions can also be used as titles of works of literature, art and scholarship. Examples include Leo Tolstoy's short story How Much Land Does a Man Need?, the painting And When Did You Last See Your Father?, the movie What About Bob?, and the academic work Who Asked the First Question?

By purpose

Various categorizations of questions have been proposed. With regard to research projects, one system distinguishes:
For the purpose of surveys, one type of question asked is the closed-ended question, usually requiring a yes/no answer or the choice of an option from a list. There are also nominal questions, designed to inquire about a level of quantitative measure, usually making connections between a number and a concept. Open-ended or open questions give the respondent greater freedom to provide information or opinions on a topic. Surveys also often contain qualifying questions, which serve to determine whether the respondent needs to continue on to answer subsequent questions.
Some types of questions that may be used in an educational context are listed in Bloom's Taxonomy of educational objectives. These include questions designed to test and promote:
McKenzie's "Questioning Toolkit" lists 17 types of questions, and suggests that thinkers need to orchestrate and combine these types. Examples of these question types include the irreverent question, the apparently irrelevant question, the hypothetical question and the unanswerable question. Questions can also be :wikt:felicitous|infelicitous, being based on incorrect and illogical premises or ill-placed premises.
Strategic studies also have taken into consideration the questioning process. In Humint, a taxonomy of questions includes:
Questions that ask whether or not some statement is true are called yes–no questions, since they can in principle be answered by a "yes" or "no". Examples include "Do you take sugar?", "Should they be believed?" and "Am I the loneliest person in the world?"
A type of question that is similar in form to a yes–no question, but is not intended to be answered with a "yes" or "no", is the alternative question. This presents two or more alternative answers, as in "Do you want fish or lamb?", or "Are you supporting England, Ireland or Wales?" The expected response is one of the alternatives, or some other indication such as "both" or "neither". Because of their similarity in form to yes–no questions, they may sometimes be answered "yes" or "no", possibly humorously or as a result of misunderstanding.
The other main type of question is those called wh-questions. These use interrogative words such as when, which, who, how, etc. to specify the information that is desired. The name derives from the fact that most of the English interrogative words begin with the letters wh. These are the types of question sometimes referred to in journalism and other investigative contexts as the Five Ws.
Tag questions are a grammatical structure in which a declarative statement or an imperative is turned into a question by adding an interrogative fragment, such as right in "You remembered the eggs, right?", or isn't it in "It's cold today, isn't it?" Tag questions may or may not be answerable with a yes or no.
As well as direct questions, there also exist indirect questions, such as where my keys are. These are used as subordinate clauses in sentences such as "I wonder where my keys are" and "Ask him where my keys are." Indirect questions do not necessarily follow the same rules of grammar as direct questions. For example, in English and some other languages, indirect questions are formed without inversion of subject and verb. Indirect questions may also be subject to the changes of tense and other changes that apply generally to indirect speech.


Languages may use both syntax and prosody to distinguish interrogative sentences from declarative sentences. Syntax refers to grammatical changes, such as moving words around or adding question words; prosody refers here to changes in intonation while speaking.
In English, German, French and various other languages, questions are marked by a distinct word order featuring inversion – the subject is placed after the verb rather than before it: "You are cold" becomes "Are you cold?" However, English allows such inversion only with a particular class of verbs, and thus sometimes requires the addition of an auxiliary do, does or did before inversion can take place – for details see do-support.
In some languages, yes–no questions are marked by an interrogative particle, such as the Japaneseka, Mandarinma and Polish czy. Also, in languages generally, wh-questions are marked by an interrogative word such as what, where or how. In languages such as English this word generally moves to the front of the sentence, and subject–verb inversion occurs as in yes–no questions, but in some other languages these changes in word order are not necessary.
Intonation patterns characteristic of questions often involve a raised pitch near the end of the sentence. In English this occurs especially for yes–no questions; it may also be used for sentences that do not have the grammatical form of questions, but are nonetheless intended to elicit information, as in "You're not using this?"
In languages written in Latin, Cyrillic or certain other scripts, a question mark at the end of a sentence identifies questions in writing. As with intonation, this feature is not restricted to sentences having the grammatical form of questions – it may also indicate a sentence's pragmatic function.


The most typical response to a question is an answer that provides the information indicated as being sought by the questioner. This may range from a simple yes or no to a more complex or detailed answer. An indication of inability or unwillingness to provide an answer is the other response to a question.
"Negative questions" are interrogative sentences which contain negation in their phrasing, such as "Shouldn't you be working?" These can have different ways of expressing affirmation and denial from the standard form of question, and they can be confusing, since it is sometimes unclear whether the answer should be the opposite of the answer to the non-negated question. For example, if one does not have a passport, both "Do you have a passport?" and "Don't you have a passport?" are properly answered with "No", despite apparently asking opposite questions. The Japanese and Korean languages avoid this ambiguity. Answering "No" to the second of these in Japanese or Korean would mean, "I do have a passport".
A similar ambiguous question in English is "Do you mind if...?" The responder may reply unambiguously "Yes, I do mind," if they do mind, or "No, I don't mind," if they don't, but a simple "No" or "Yes" answer can lead to confusion, as a single "No" can seem like a "Yes, I do mind", and a "Yes" can seem like a "No, I don't mind". An easy way to bypass this confusion would be to ask a non-negative question, such as "Is it all right with you if...?"
Some languages have different particles to answer negative questions in an affirmative way; they provide a means to express contradiction.
In the interest of precise language, a direct answer has been defined:
"A direct answer to a given question is a piece of language that completely, but just completely, answers the question...What is crucial is that it be effectively decidable whether a piece of language is a direct answer to a specific question." and "To each clear question there corresponds a set of statements which are directly responsive.... A direct answer must provide an unarguably final resolution of the question."
More information on these issues can be found in the articles yes–no question, yes and no, and answer ellipsis.


Questions are used from the most elementary stage of learning to original research. In the scientific method, a question often forms the basis of the investigation and can be considered a transition between the observation and hypothesis stages. Students of all ages use questions in their learning of topics, and the skill of having learners creating "investigatable" questions is a central part of inquiry education. The Socratic method of questioning student responses may be used by a teacher to lead the student towards the truth without direct instruction, and also helps students to form logical conclusions.
A widespread and accepted use of questions in an educational context is the assessment of students' knowledge through exams.


questions are conceptual, not factual questions. There are questions that are not fully answered by any other. Philosophy deals with questions that arise when people reflect on their lives and their world. Some philosophical questions are practical: for example, "Is euthanasia justifiable?", "Does the state have the right to censor pornography or restrict tobacco advertising?", "To what extent are Māori and Pākehā today responsible for decisions made by their ancestors?"
Other philosophical questions are more theoretical, although they often arise through thinking about practical issues. The questions just listed, for example, may prompt more general philosophical questions about the circumstances under which it may be morally justifiable to take a life, or about the extent to which the state may restrict the liberty of the individual. Some "classic" questions of philosophy are speculative and theoretical and concern the nature of knowledge, reality and human existence: for example, "What, if anything, can be known with certainty?", "Is the mind essentially non-physical?", "Are values absolute or relative?", "Does the universe need explanation in terms of a Supreme Intelligence?", "What, if anything, is the meaning or purpose of human existence?" Finally, the philosophical questions are typically about conceptual issues; they are often questions about our concepts and the relation between our concepts and the world they represent. Every question implies a statement and every statement implies a question.


Enculturated apes Kanzi, Washoe, Sarah and a few others who underwent extensive language training programs successfully learned to answer quite complex questions and requests, although so far they have failed to learn how to ask questions themselves. For example, David and Anne Premack wrote: "Though she understood the question, she did not herself ask any questions — unlike the child who asks interminable questions, such as What that? Who making noise? When Daddy come home? Me go Granny's house? Where puppy? Sarah never delayed the departure of her trainer after her lessons by asking where the trainer was going, when she was returning, or anything else". The ability to ask questions is often assessed in relation to comprehension of syntactic structures. It is widely accepted that the first questions are asked by humans during their early infancy, at the pre-syntactic, one word stage of language development, with the use of question intonation.