Changing the World on the Server

To create new data (like a comment or user), send it in the request body.

async function createPost(title, body) {
  const response = await fetch('https://jsonplaceholder.typicode.com/posts', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({ title, body, userId: 1 })
  });

  const newPost = await response.json();
  console.log('Created:', newPost.id); // Server assigns an ID
  return newPost;
}

Updating Data (PATCH / PUT)

// PATCH — partial update (only fields you provide change)
await fetch('/api/users/42', {
  method: 'PATCH',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({ email: 'new@email.com' }) // Only email changes
});

// PUT — full replacement (all fields must be provided)
await fetch('/api/users/42', {
  method: 'PUT',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({ name: 'Alice', email: 'alice@example.com', age: 28 })
});