What is State?

This counter has a bug that produces no error message. Its variable goes up with every press, but the number on the screen never changes:

import { Button, Text, View } from 'react-native';

function Counter() {
  let count = 0;

  const handlePress = () => {
    count = count + 1;
    console.log('count is now', count);
  };

  return (
    <View>
      <Text>Count: {count}</Text>
      <Button title="Increment" onPress={handlePress} />
    </View>
  );
}

Three presses produce this output, while the screen still shows Count: 0:

count is now 1
count is now 2