python variable definition and literal

Hello this is Juny.

python variable is dynamic typing variable.

when you declare any variable, the type of variable is not needed.

let's learn what is variable and

how to declare variable.

let's start.

variable

variable is a indentifier for literal.

we say that we align a value to variable in programming.

in other words, we name it.

for example,

there is 3 value.

and we can call it A.

as a result, A will be variable or identifier for 3.

let's see code.

A=3

we can declare variable like above.

but, there are some rules to name variable.

• it cannot begin with numbers.
• you can use alphabet, numbers and underscore(_).
• capital of alphabet is important. 

for example,

• 1var (X)
• 0abc (X)
• abc1 (O)
• _ab (O)
• aaa (O)
• my_name (O)
• abc-def (X)
• abc% (X)
• AAA (O)
• Aaa (O)

let's check one of them.

AA = 3
aa = 2
Aa = 1
print(AA ,aa ,Aa )

3 variables are declared.

they have same alphabet A.

but, capital is different from each other.

I print each variable to console.

each variable has each value.

literal

literal is representation of value.

for example,

if we assign 3 to A, 3 is literal.

for another example,

if we assign "hello" to B, "hello" is literal.

if we don't assign literal to any variable,

we cannot have reference for the literal.

if you want to reuse the literal,

you have to assign it to any variable.

let's check it in code.

A = 1
2
3
B = "hello"
"bye"
print(A)
print(B)

1 is assigned to A.

2 and 3 is not assigned.

"hello" is assigned to B.

"Bye" is not assigned.

the variables are printed out to console.

literals cannot be printed.

because there is no way to call them.

1 and "hello" are printed out successfully.