Check out example codes for "curl post request". It will help you in understanding the concepts better.

Code Example 1

curl -d "user=user1&pass=abcd" -X POST https://example.com/login

Code Example 2

curl -d '{"key1":"value1", "key2":"value2"}' -H "Content-Type: application/json" -X POST http://localhost:3000/data

Code Example 3

$data = [
				'api_key' => '123456789',
				'name' => 'Emmanuel',
				'email'   => '[email protected]'
				];
			$url = 'https://mysite.com/api/subscribe';
			$ch = curl_init();
			curl_setopt($ch, CURLOPT_URL, $url);
			curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
			curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($data));
			$response = curl_exec($ch);
			var_export($response);

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