I am refering to this particular question. I had suggested a link to MFCC on Wikipedia in a comment but to see no improvement. If i put myself in the shoes of an expert, I feel extremely annoyed and repulsive to questions and answers like this. More over when i think of the up votes of these posts in this Q&A, i am worried where this site is heading to. I'd appreciate your comments on this.
Added : (..in view of comment below) The OP is seeking explanation of how a speech signal is represented by a feature vector. The most commonly used feature for speech recognition is MFCC, although there are many systems which use different types of features. The method of extracting the MFCC feature from speech signal is given in this link very clearly. In this answer the answerer starts with the tool called 'HTK' which is not relevant to the question directly and further does not bother to mention any reference or link to it. Then he goes on to say how speech recognition is carried on in brain and claims that it is very similar to that being done with this tool called 'HTK'. Here itself you can see how irrelavant it is to the particular question and he creates more chaos further in the answer by trying to explain the speech recognition method. It heavily lacks scientific method and is very annoying.
The OP mentions in the question that he understands HMM based speech recognition to some extent, without knowing what a feature vector is ? I wonder to what extent he understands. He does not mention any home work he did before asking the question. A HMM based speech recognition can use any type of feature vector and not necessarily MFCC, and if one has to answer this question he should presume it to be something which is popular and hence MFCC could be one choice. There are so many irrelevant things in these posts which i am tired to mention.
I have mentioned a link to a Wikipedia article on MFCC in a comment, which is very decent by all standards, but no one seems to acknowledge it and some have blidly upvoted the answer. I find these posts to be quite ridiculous and I am sure if this goes on, no expert in the field want to be associated with this site and further some of the existing members upvote each other and think of themselves as experts. I am not bothered by the correctness of the posts but the irrationality in these posts and upvotes.