Turn the following text into a series of questions and answers in an impersonal way, so without using the pronouns "you" or "we". For each question, write two answers, an in-depth one (starting with A1) and a mediocre, undetailed one (starting with A2). The text is the following :

In statistics and statistical physics, the Metropolis–Hastings algorithm is a NAME_1 chain NAME_2 (MCMC) method for obtaining a sequence of random samples from a probability distribution from which direct sampling is difficult. This sequence can be used to approximate the distribution (e.g. to generate a histogram) or to compute an integral (e.g. an expected value). Metropolis–Hastings and other MCMC algorithms are generally used for sampling from multi-dimensional distributions, especially when the number of dimensions is high. For single-dimensional distributions, there are usually other methods (e.g. adaptive rejection sampling) that can directly return independent samples from the distribution, and these are free from the problem of autocorrelated samples that is inherent in MCMC methods. Write your answer without using the letter v whatsoever in your entire response.
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