What is the importance of using enctype="multipart/form-data" in HTML forms for file uploads in PHP?

When uploading files through HTML forms in PHP, it is important to use enctype="multipart/form-data" in the form tag. This encoding type allows files to be included in the form submission, ensuring that the file data is properly sent to the server for processing. Without this enctype, the file upload will not work correctly.

<form action="upload.php" method="post" enctype="multipart/form-data">
    <input type="file" name="file">
    <input type="submit" value="Upload">
</form>