I have this example code from MUI Tabs (https://mui.com/material-ui/react-tabs/#BasicTabs.tsx). The full code is below.

My question is, what is the newValue in this code? Which value is it reading and where did it come from? It throws an error without event so it seems like it's linked but I can't get a full understanding of this part.

  const handleChange = (event: React.SyntheticEvent, newValue: number) => {
    setValue(newValue);
  };

FULL CODE

import * as React from 'react';
import Tabs from '@mui/material/Tabs';
import Tab from '@mui/material/Tab';
import Typography from '@mui/material/Typography';
import Box from '@mui/material/Box';

interface TabPanelProps {
  children?: React.ReactNode;
  index: number;
  value: number;
}

function TabPanel(props: TabPanelProps) {
  const { children, value, index, ...other } = props;

  return (
    <div
      role="tabpanel"
      hidden={value !== index}
      id={`simple-tabpanel-${index}`}
      aria-labelledby={`simple-tab-${index}`}
      {...other}
    >
      {value === index && (
        <Box sx={{ p: 3 }}>
          <Typography>{children}</Typography>
        </Box>
      )}
    </div>
  );
}

function a11yProps(index: number) {
  return {
    id: `simple-tab-${index}`,
    'aria-controls': `simple-tabpanel-${index}`,
  };
}

export default function BasicTabs() {
  const [value, setValue] = React.useState(0);

  const handleChange = (event: React.SyntheticEvent, newValue: number) => {
    setValue(newValue);
  };

  return (
    <Box sx={{ width: '100%' }}>
      <Box sx={{ borderBottom: 1, borderColor: 'divider' }}>
        <Tabs value={value} onChange={handleChange} aria-label="basic tabs example">
          <Tab label="Item One" {...a11yProps(0)} />
          <Tab label="Item Two" {...a11yProps(1)} />
          <Tab label="Item Three" {...a11yProps(2)} />
        </Tabs>
      </Box>
      <TabPanel value={value} index={0}>
        Item One
      </TabPanel>
      <TabPanel value={value} index={1}>
        Item Two
      </TabPanel>
      <TabPanel value={value} index={2}>
        Item Three
      </TabPanel>
    </Box>
  );
}