Question

Repeated slicing works on tuples and lists just fine:

>>> tuple = ("nav", "yad")
>>> tuple[0]
'nav'
>>> tuple[0][0]
'n'

But with strings:

>>> name="university"
>>> name[0]
'u'

The weird thing here is, when I try repeated slicing over string name variable,
there is nothing at name[0][0] or name[0][-1], so why does it show "u"?

>>> name[0][0]
'u'
>>> name[0][-1]
'u'

And if something is at name[0][0] then why not on other indexes?

>>> name[0][1]
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
IndexError: string index out of range

Answer 1

String is a sequence. String of one character is still a sequence with one element. So with a string you can do name[0][0][0][0]... and it will work fine. Same with index -1, that returns last element of a sequence:

>>> name[0][0]
'u'
>>> name[0][0][-1]
'u'
>>> name[0][0][-1][-1]
'u'

name[0][1] obviously fails because there is only one element in the string name[0].