DOC: Improve Index docstrings (#36239)

Author: Nikhil1O1

pandas/core/indexes/base.py

@@ -195,7 +195,7 @@ def _new_Index(cls, d):
 
 class Index(IndexOpsMixin, PandasObject):
     """
-    Immutable ndarray implementing an ordered, sliceable set. The basic object
+    Immutable sequence used for indexing and alignment. The basic object
     storing axis labels for all pandas objects.
 
     Parameters

pandas/core/indexes/numeric.py

@@ -189,7 +189,7 @@ def _union(self, other, sort):
 _num_index_shared_docs[
     "class_descr"
 ] = """
-    Immutable ndarray implementing an ordered, sliceable set. The basic object
+    Immutable sequence used for indexing and alignment. The basic object
     storing axis labels for all pandas objects. %(klass)s is a special case
     of `Index` with purely %(ltype)s labels. %(extra)s.