Question: ```
this.setState({
      object1: { ...object2 },
});

```

I know it does something to the state. but I'm not able to understand what it means? Is this a technique in JS/React?

Answer: 
You are essentially setting `object1` to be the same as `object2` via [spread syntax](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Spread_syntax#Syntax). For example:

```
this.state = { object1: { hello: 'world' } };

const object2 = { foo: 'bar' };

this.setState({ object1: { ...object2 } });

```

this would result in the state to be:

```
{ object1: { foo: 'bar' };

```
This is spread operator and you can read more about it here

<https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Spread_syntax#Spread_in_object_literals>[enter link description here](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Spread_syntax#Spread_in_object_literals)

The setState in your code is updating the current state variable object1 with the values from object2