Retrieve the requested data of the author of the current post.

Signature

get_the_author_meta( $field = '', $user_id = false )
field
 (string) selects the field of the users record.
Default: ''
user_id
 (int) Optional. User ID.
Default: false

Return

(string) The author's field from the current author's DB object.

Source

function get_the_author_meta( $field = '', $user_id = false ) {
	if ( ! $user_id ) {
		global $authordata;
		$user_id = isset( $authordata->ID ) ? $authordata->ID : 0;
	} else {
		$authordata = get_userdata( $user_id );
	}

	if ( in_array( $field, array( 'login', 'pass', 'nicename', 'email', 'url', 'registered', 'activation_key', 'status' ) ) )
		$field = 'user_' . $field;

	$value = isset( $authordata->$field ) ? $authordata->$field : '';

	/**
	 * Filter the value of the requested user metadata.
	 *
	 * The filter name is dynamic and depends on the $field parameter of the function.
	 *
	 * @since 2.8.0
	 *
	 * @param string $value   The value of the metadata.
	 * @param int    $user_id The user ID.
	 */
	return apply_filters( 'get_the_author_' . $field, $value, $user_id );
}
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