this.props.children vs this.props.someName - reactjs

Question

It seems, I see two equal ways to delegate property via props:
let App = React.createClass({
render(){
return (
<Unit someName="Push me!" />
)
}
});
class Unit extends React.Component{
render(){
return (
<button>
<span className="glyphicon glyphicon-heart"/>
{this.props.someName}
</button>
)
}
};
and
let App = React.createClass({
render(){
return(
<Unit>
<span className="glyphicon glyphicon-heart"></span>
Push me now!
</Unit>
)
}
});
class Unit extends React.Component{
render(){
return (
<button>{this.props.children}</button>
)
}
};
What's the general purpose of props.children?
Can I consider it as equal to props.someName?
Could be provided some examples where props.someName doesn't work but props.childred does?

Answer 1

Maybe I am wrong, but I think that the existence of children is just syntactic sugar to allow an HTML-like nesting of elements. As far as I know, it is exactly the same as any other property. In fact, while using JSX you can add children as an ordinary property and it doesn't make any difference.
let App = React.createClass({
render(){
return(
<Unit children={<span className="glyphicon glyphicon-heart">Push me now!</span>}/>
)
}
});
class Unit extends React.Component{
render(){
return (
<button >{this.props.children}</button>
)
}
};
ReactDOM.render(<App/>, document.getElementById('app'));
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id="app"></div>

Answer 2

Generally speaking, this.props.children is used to refer to all the children that are wrapped in a custom component.
<View>
<Text>One</Text>
<Text>Two<Text>
</View>
Here, the two Text elements are children to your View. In the class definition(or equivalent) for your View component, you can refer to all the children components by this.props.children. But I think you already understand this much.
From what I understand, as a rule of thumb, you pass some values/properties, etc as props to a component.
If you want to, for example, render some components in a custom component that you are defining, you need to be able to refer to what components were declared in the implementation code from definition code, so you use this.props.children.
My language is a bit muddled, but I hope this is clear enough.