What do mean by indexing in python? And what does backward and forward indexing signify??

Answer 1

Indexing simply refers to giving your elements in any sequence(list, tuple, string etc.) some address so that we can retrieve them. Eg

List1 = [1,3,4,8,2]
Print(list1[1])

#since we are putting the parameter in square bracket which means the parameter is our index.
O/p - 3
Bcoz the indexing in list starts from 0.
I.e. index and elements
0 - 1
1 - 3
2 - 4
3 - 8
4 - 2

in the above program python looks for element in index number 1.

Answer 2

list_2= [5,2,1,8]

forward indexing is in simple terms using +ve numbers for indexing and backward indexing is using -ve numbers.

element ~ forward index ~ backward index
5 ~ 0 ~ -1
2 ~ 1 ~ -2
1 ~ 2 ~ -3
8 ~ 3 ~ -4

eg: print(list_2[-3])
o/p- 1

#plz up vote and tick is you like explanation it takes quite some time to write.