In Christian tradition this refers to the virgin birth of Jesus and frequently read in Christmas services. The context of this is the conversation between Isaiah and Ahaz, Jerusalem's king at the time of the Arameans and son of Remaliah's attack to Jerusalem's. Ahaz is asking for sign that he will be protected and this is given as sign.
Much has been discussed on this throughout the history, I am sure, and I have not read any of it. So I am not sure whether I should comment about it but as a Christian, I am being held accountable to God and my conscience and I personally have a problem with this.
On one hand, the word virgin in is the same as maid girl in Aramaic, and apparently was more common to be used as the maid girl. On the other hand, the context is completely different. And the talk about eating butter and honey (perhaps reference to the abundance in the land of Israel), and desolation of the lands of the kings attacking which is supposed to happen during the time the boy is prepubescent.
On the other hand, it is strange that such a boy is not referred to later in the text which is bizarre too.
More on that tomorrow.