how to use loc and iloc in pandas

1>>> s = pd.Series(list("abcdef"), index=[49, 48, 47, 0, 1, 2]) 
249    a
348    b
447    c
50     d
61     e
72     f
8
9>>> s.loc[0]    # value at index label 0
10'd'
11
12>>> s.iloc[0]   # value at index location 0
13'a'
14
15>>> s.loc[0:1]  # rows at index labels between 0 and 1 (inclusive)
160    d
171    e
18
19>>> s.iloc[0:1] # rows at index location between 0 and 1 (exclusive)
2049    a
21

1iloc - default indexes (system generated)
2loc - table indexes or we manually given indexes 

1>>> df.iloc[0, 1]
22
3