What is a variable?
• A variable refers to memory location.
• It is used to store the value .
• Variable is used to give data to the computer for processing .
Specifying a variable
• In python we don’t need to specify the type of variable because python isa dynamically typed to get variable type.
• Variable names include letters and digits but they have to begin with a letter or an underscore.
• It is suggested to use lowercase letters for variable name.
Types of variables
There are two types of variables in python local and global variables.
• In Python, global variable is a variable declared outside of the function or in global scope.
• global variable can be accessed inside or outside of the scope function
Local variables
Local variables are the variables that are used with in a function or method.
Global variables
Global variables are used when we use the variable in the entire program.
Assigning values to variables
• Python allows us to assign values to the variables.
• Lets assume the value 5 is assigned to the variable ‘a’
Multiple assignment
• in multiple assignment , multiple variables are assigned with multiple values.
Example
Declaring and re-declaring the variables.
• Lets first see how to declare a variable. Its that simple that assigning variable a value to hold.
• Example
a=9
print(a)
9
• Now we re declare the variable.
• a=9
print(a)
a= 33
print(a)
output:
33
Here the output gives the re assigned value instead of first value. This means that the firstvalue is replaced by second value.
Deleting the variable
• In python you can delete the variable that you previously assigned the value using del command.
Example
a=7
print(a)
del a
print(a)