All language subtitles for 006 Dynamic vs. Static Typing_en

In the last lectures, we talked about the basics of variables.

What is the variable?

What is the purpose of a variable and how to declare variables.

Now we'll take a look at what type of data can be stored in a variable.

Python is a dynamically typed programming language, and this is in contrast to C, C++, Java or GO,

which are statically typed.

A language is statically typed.

If the type of a variable is known at compile time or before running the program.

This is Java code.

Before running this program, I know that the variable score is of typing.

This means that the parameter must specify the type of data that will be stored in the variable when

he defines the variable in a statically typed language like Java.

A variable would be declared as an int score and then defined as score equals ten.

I'm running the program.

A language like Python is dynamically typed and it means that the type is associated with runtime values

and not with named variables.

So the values stored in variables have types and not the name or the variable itself.

This means that you as a developer can write code a little bit quicker because you never have to specify

variable types.

In Python, we create a variable named score simply by writing a score equals ten.

We can see what type of data a variable stores using the built in function type.

Print type of score.

For example, this is of typing.

Each variable or object.

A variable is in fact an object or an instance of a class has a type of value and an ID, and they are

constant during the variable lifetime.

I am declaring another variable A equals five and print type of A and then a equals python.

And print type of a.

A was of type in and then of type STR.

In fact they are different variables or were saved at different addresses.

Earlier, I said that the variable has a constant ID.

What is that ID and how do we get it?

The builtin function ID returns the memory address where the value referenced by the variable is stored

or simply said.

This is the address of the variable in memory.

If I write, my var equals ten.

Then my var is the reference to an integer object containing the value ten and is located at the memory

address returned by the ID function.

Now this is memory address.

In conclusion, statically typed languages have better performance at runtime and are faster.

This is because there is no need for type checking at runtime, but dynamically typed languages are

comparatively faster during development time and are more flexible.

Of exit.

In this video, you will learn the differences between statically and dynamically typed programming

languages, and that python is the dynamically typed one.

Next, we'll move to built in data types.

I'll see you soon.