Could you explain the meaning of the sentence

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The $X$ set explanationThe sentence itself

My native language is not English and can't realize what does the first sentence on the picture sentence mean. In particular, "each angle and the $x$ axis are components". Could you explain it in other words?

Thank you!

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They are talking about connected components here. The set $X$ consists of the $x$-axis, along with infinitely many "angles". An angle in this case means one horizontal ray, meeting a line segment from $(0,1)$ at an angle. Here is a hastily-drawn picture of one such "angle":

enter image description here

As you can see from the drawing in your book, $X$ consists of infinitely many such angles, all joined together at $(0,1)$.

If you remove $(0,1)$ from this space, then each of those angles will be connected omponents of the space that is left.