What are potential ethical concerns when extracting information from external websites for personal use?

Potential ethical concerns when extracting information from external websites for personal use include violating the website's terms of service, infringing on intellectual property rights, and potentially causing harm to the website or its users by overloading the server with excessive requests. To address these concerns, it is important to always respect the terms of service of the website, obtain permission if necessary, and ensure that your web scraping activities do not disrupt the normal functioning of the website.

// Example PHP code snippet demonstrating ethical web scraping practices
// Make sure to read and comply with the website's terms of service before scraping

$url = 'https://www.example.com';
$user_agent = 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.110 Safari/537.3';
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_USERAGENT, $user_agent);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
$output = curl_exec($ch);
curl_close($ch);

// Process the extracted information here