GraphQL features I found

Now I am learning GraphQL myself.
At first, I couldn't understand what it was and why it is needed.
We already have REST API, and why do we need GraphQL?
And I kept reading the documents over and over and now, I finally get to know what it is and how to use it.
Of course, I admit that it is much more powerful and useful than REST API.
And I am pretty sure it will replace all the REST APIs, sooner or later.

So what are the main features I found?
There are 2 features that I found most useful and powerful in GraphQL.

One is that it uses one endpoint. Thanks to this feature, it's quite flexible working with GraphQL queries.

And the other is it has subscription features.
An important requirement for many applications today is to have a realtime connection to the server in order to get immediately informed about important events.
For this use case, GraphQL offers the concept of subscriptions.
It just opens a new steady connection to the server, and whenever a particular event happens, the server pushes the corresponding data to the client.

I am still a newbie in GraphQL class, so I hope your advice on my article.
Thanks.