What does axis in pandas mean?

Here is my code to generate a dataframe:

    import pandas as pd
    import numpy as np

    dff = pd.DataFrame(np.random.randn(1,2),columns=list('AB'))

then I got the dataframe:

    +------------+---------+--------+
    |            |  A      |  B     |
    +------------+---------+---------
    |      0     | 0.626386| 1.52325|
    +------------+---------+--------+

When I type the commmand :

    dff.mean(axis=1)

I got :

    0    1.074821
    dtype: float64

According to the reference of pandas, axis=1 stands for columns and I expect the result of the command to be

    A    0.626386
    B    1.523255
    dtype: float64

So here is my question: what does axis in pandas mean?

It specifies the axis along which the means are computed. By default axis=0. This is consistent with the numpy.mean usage when axis is specified explicitly (in numpy.mean, axis==None by default, which computes the mean value over the flattened array) , in which axis=0 along the rows (namely, index in pandas), and axis=1 along the columns. For added clarity, one may choose to specify axis='index' (instead of axis=0) or axis='columns' (instead of axis=1).

    +------------+---------+--------+
    |            |  A      |  B     |
    +------------+---------+---------
    |      0     | 0.626386| 1.52325|----axis=1----->
    +------------+---------+--------+
                 |         |
                 | axis=0  |
                          

From: stackoverflow.com/q/22149584

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