Question 1174279
<pre>
Ikleyn is not aware of the inconsistencies in geometry notation. Copied and pasted from:
 
https://www.mathstips.com/point-ray-line-and-line-segment/

<I>A line is named by any two points on it and written as line AB or line PQ.
One and only one line can be drawn passing through two given points A and B.
This line is called AB. It may also be called BA.  Line BA is the same as line
AB. Both pass through the same two points A and B.</i>

In other places, the notation is different.  Often line segments are called "lines".

In my many years of teaching mathematics, I have discovered that notation in
mathematics is very often inconsistent.  Also some books use "equal" for lines
and angles, and "congruent" only for closed figures, whereas others use
"congruent" for them all.  Nothing is written in stone.

As another example of inconsistency, does (1,2) represent a point or an open
interval?  We can only go by context.  

Edwin</pre>