Can someone help me in understanding the values of alphabets as per numerology?!

Can someone help me in understanding the values of alphabets as per numerology?

I got to know that there are three different methodologies used in associating a value to alphabets as per numerology. Wanted to know which one to use as per Indian Numerology practioners

Numerology
The mystical attraction of basic qualities of numbers resulted in strange theories about magical powers that could be invoked or discovered by carrying out certain arithmetical operations. Such a belief, based on an idea of Pythagoras that all facts can be reduced to numbers, results from a failure to understand the true nature of the concept of number.
In applying numerology to a person's name, for example, there are many different systems in this “art” for assigning numbers to the letters of the alphabet, adding them up and arriving at a series of qualities, characteristics, and specific facts that are said to apply to that person. The dubious nature of the practice becomes obvious.
Three of the most popular systems among many, many such systems to determine “name numbers” are shown here:

A = 1 1 1
B = 2 5 2
C = 3 6 3
D = 4 9 4
E = 5 3 5
F = 8 8 6
G = 3 8 7
H = 5 3 8
I = 1 9 9
J = 1 9 1
K = 2 6 2
L = 3 5 3
M = 4 7 4
N = 5 7 5
O = 7 1 6
P = 8 5 7
Q = 1 6 8
R = 2 9 9
S = 3 3 1
T = 4 8 2
U = 6 8 3
V = 6 3 4
W = 6 3 5
X = 0 9 6
Y = 1 6 7
Z = 7 5 8

The third column of numbers represents what is known as the Pythagorean system. All of these systems require the user to add together each of the digits representing each letter in the name, then to add the digits of the resulting number, and repeat that process until a number less than 10 has been arrived at. This final digit is interpreted according to the following table:

1 —— action, aggression, ambition, leadership, purpose
2 —— balance, passivity, receptivity
3 —— brilliance, gaiety, versatility
4 —— dullness, endurance, steadiness
5 —— adventure, instability, sexuality
6 —— dependability, domesticity, harmony
7 —— knowledge, mystery, solitariness
8 —— material success, worldly involvement
9 —— great achievement, inspiration, spirituality

It can be seen that there is no standard and no consistency in numerology——let alone rationality——but it provides an easy method for the naive person to play a satisfying game without having to apply any intellectual powers to the matter.
Gematria is a form of numerology which employs the Hebrew alphabet, in which all the letters also have numerical values.
Modern numerologists, quick to adopt new technologies to prove and enlarge old claptrap, have now turned to a computer number system, the American Standard for Coded Interchange of Information (ASCII), for further deep meaning of the alphabet.