The line at 1/2 could mean one of several things..........1d to 2d........single digits to double digits, etc.............................the last prime in double digits.......97...........is 16.............adding its double digit to its single digits........9 + 7 = 16...................9 is the last number in single digits..........7 is the last prime in double digits..........a double helix...............two twists.................two spirals..........intertwined..................two things put together.............different yet similar...................asymmetry and symmetry at once..............................2, 3, 5, 7.................2 and 3 are the only two primes..........EVER but a number apart....................2 + 3 + 5 + 7 = 17................all single digit primes.................sum to 17......................adding 11..............it becomes half of the prime fund........one of them.........what I call the prime fundamental anyways.............2 + 3 + 5 + 7 + 11 = 28..........................28 is in a lot of this as well................and it is the 2nd perfect number........28 is in e twice...........28 + 28 = 56............reflexive sym with 65.............the sum of 2 - 11..................primes and non primes........................................

e (Euler's Number)

The number e is a famous irrational number, and is one of the most important numbers in mathematics.
The first few digits are:

2.7182818284590452353602874713527 (and more ...)

It is often called Euler's number after Leonhard Euler (pronounced "Oiler").

e is the base of the Natural Logarithms (invented by John Napier).
e is found in many interesting areas, so it is worth learning about.