Python "None"
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JacksonCowie (278)

The keywords Null and None. If you are new to programming you may think they mean zero, they do not. On first sight they look alike, so what's the difference?

In many programming languages (C, Java, SQL, JavaScript) there is a Null value. Sometimes explicitly spelled as NULL or null.

Not so in Python, Python does not have a null value.

>>> x = null
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'null' is not defined
>>> 

###None type

Instead there is the None object. None effectively means there is no value or it is empty. Basically, NoneType is a data type just like int, float, etc.

You can see a type using:

 >>> print(type(int))
    <class 'type'>
    >>> print(type(float))
    <class 'type'>

You can see this for the None type too:

>>> print(type(None))
    <class 'NoneType'>

###Assign None value
You can see above is an object (class), in Python this None object never has any functionality. Lets define a variable with the None value:

>>> twelve = None
    >>> print(twelve is None)
    True
    >>> 

None means no value, not zero.

 >>> print(twelve == 0)
    False

###None and null difference
Although there is no null value in Python, you can use None like null.

  >>> x = None
    >>> if x is None:
    ...     print('x is null')
    ... else:
    ...     print('x is not null')
    ... 
    x is null

I just realised how rubbish this post was, I'm sorry.

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LiamDonohue (220)

null (none) just means that the variable does not have a value

JacksonCowie (278)

@LiamDonohue Yes, but I just explained it in more detail.