A simple counter, made using React functional components and typescript

FunctionalCounter.tsx

import React, { FC, useState } from "react";

interface Props {
  title: string;
  initialCount: number;
}

const FunctionalCounter: FC<Props> = ({ title, initialCount }) => {
  const [count, setCount] = useState(initialCount);

  const add = (factor = 1) => {
    setCount(count + factor);
  };

  return (
    <div>
      <h1>{title}</h1>
      <h2>{count}</h2>
      <button onClick={() => add()}>+</button>
      <button onClick={() => add(-1)}>-</button>
    </div>
  );
};

export default FunctionalCounter;