diff --git a/framework/helpers/BaseUrl.php b/framework/helpers/BaseUrl.php
index 9392517408..8712a655c3 100644
--- a/framework/helpers/BaseUrl.php
+++ b/framework/helpers/BaseUrl.php
@@ -7,8 +7,9 @@
 
 namespace yii\helpers;
 
-use yii\base\InvalidParamException;
 use Yii;
+use yii\base\InvalidParamException;
+use yii\web\Controller;
 
 /**
  * BaseUrl provides concrete implementation for [[Url]].
@@ -26,9 +27,9 @@ class BaseUrl
 	 * @param array|string $route route as a string or route and parameters in form of
 	 * `['route', 'param1' => 'value1', 'param2' => 'value2']`.
 	 *
-	 * If there is a controller running relative routes are recognized:
+	 * If there is a controller running, relative routes are recognized:
 	 *
-	 * - If the route is an empty string, the current [[\yii\web\Controller::route]] will be used;
+	 * - If the route is an empty string, the current [[\yii\web\Controller::route|route]] will be used;
 	 * - If the route contains no slashes at all, it is considered to be an action ID
 	 *   of the current controller and will be prepended with [[\yii\web\Controller::uniqueId]];
 	 * - If the route has no leading slash, it is considered to be a route relative
@@ -36,26 +37,26 @@ class BaseUrl
 	 *
 	 * In case there is no controller, [[\yii\web\UrlManager::createUrl()]] will be used.
 	 *
-	 * @param boolean|string $schema URI schema to use:
+	 * @param boolean|string $scheme URI scheme to use:
 	 *
 	 * - `false`: relative URL. Default behavior.
 	 * - `true`: absolute URL with the current scheme.
-	 * - string: absolute URL with string value used as schema.
+	 * - string: absolute URL with string value used as scheme.
 	 *
-	 * @return string the normalized URL
+	 * @return string the URL for the route
 	 * @throws InvalidParamException if the parameter is invalid.
 	 */
-	public static function toRoute($route, $schema = false)
+	public static function toRoute($route, $scheme = false)
 	{
 		$route = (array)$route;
-		if (Yii::$app->controller instanceof \yii\web\Controller) {
+		if (Yii::$app->controller instanceof Controller) {
 			$route[0] = static::getNormalizedRoute($route[0]);
 		}
-		if ($schema) {
-			if ($schema === true) {
-				$schema = null;
+		if ($scheme) {
+			if ($scheme === true) {
+				$scheme = null;
 			}
-			$url = Yii::$app->getUrlManager()->createAbsoluteUrl($route, $schema);
+			$url = Yii::$app->getUrlManager()->createAbsoluteUrl($route, $scheme);
 		} else {
 			$url = Yii::$app->getUrlManager()->createUrl($route);
 		}
@@ -63,12 +64,12 @@ class BaseUrl
 	}
 
 	/**
-	 * Normalizes route making it suitable for UrlManager. Absolute routes are staying as is
-	 * while relative routes are converted to absolute routes.
+	 * Normalizes route and makes it suitable for UrlManager. Absolute routes are staying as is
+	 * while relative routes are converted to absolute ones.
 	 *
 	 * A relative route is a route without a leading slash, such as "view", "post/view".
 	 *
-	 * - If the route is an empty string, the current [[\yii\web\Controller::route]] will be used;
+	 * - If the route is an empty string, the current [[\yii\web\Controller::route|route]] will be used;
 	 * - If the route contains no slashes at all, it is considered to be an action ID
 	 *   of the current controller and will be prepended with [[\yii\web\Controller::uniqueId]];
 	 * - If the route has no leading slash, it is considered to be a route relative
@@ -90,36 +91,36 @@ class BaseUrl
 	}
 
 	/**
-	 * Creates a link specified by the input parameter.
+	 * Creates a URL specified by the input parameter.
 	 *
-	 * If the input parameter
+	 * If the input parameter is
 	 *
-	 * - is an array: the first array element is considered a route, while the rest of the name-value
-	 *   pairs are treated as the parameters to be used for URL creation using [[toRoute]].
+	 * - an array: the first array element is considered a route, while the rest of the name-value
+	 *   pairs are treated as the parameters to be used for URL creation using [[toRoute()]].
 	 *   For example: `['post/index', 'page' => 2]`, `['index']`.
 	 *   In case there is no controller, [[\yii\web\UrlManager::createUrl()]] will be used.
-	 * - is an empty string: the currently requested URL will be returned;
-	 * - is a non-empty string: it will first be processed by [[Yii::getAlias()]]. If the result
-	 *   is an absolute URL, it will be returned either without any change or, if schema was specified, with schema
+	 * - an empty string: the currently requested URL will be returned;
+	 * - a non-empty string: it will first be processed by [[Yii::getAlias()]]. If the result
+	 *   is an absolute URL, it will be returned either without any change or, if scheme was specified, with scheme
 	 *   replaced; Otherwise, the result will be prefixed with [[\yii\web\Request::baseUrl]] and returned.
 
 	 *
 	 * @param array|string $url the parameter to be used to generate a valid URL
-	 * @param boolean|string $schema URI schema to use:
+	 * @param boolean|string $scheme URI scheme to use:
 	 *
 	 * - `false`: relative URL. Default behavior.
 	 * - `true`: absolute URL with the current scheme.
-	 * - string: absolute URL with string value used as schema.
+	 * - string: absolute URL with string value used as scheme.
 	 *
 	 * @return string the normalized URL
 	 * @throws InvalidParamException if the parameter is invalid.
 	 */
-	public static function to($url = '', $schema = false)
+	public static function to($url = '', $scheme = false)
 	{
 		if (is_array($url)) {
-			return static::toRoute($url, $schema);
+			return static::toRoute($url, $scheme);
 		} elseif ($url === '') {
-			if ($schema) {
+			if ($scheme) {
 				$url = Yii::$app->getRequest()->getAbsoluteUrl();
 			} else {
 				$url = Yii::$app->getRequest()->getUrl();
@@ -130,25 +131,26 @@ class BaseUrl
 				if ($url === '' || ($url[0] !== '/' && $url[0] !== '#' && strncmp($url, './', 2))) {
 					$url = Yii::$app->getRequest()->getBaseUrl() . '/' . $url;
 				}
-				if ($schema) {
+				if ($scheme) {
 					$url = Yii::$app->getRequest()->getHostInfo() . $url;
 				}
 			}
 		}
-		if ($schema && $schema !== true) {
+		if ($scheme && $scheme !== true) {
 			$pos = strpos($url, '://');
 			if ($pos !== false) {
-				$url = $schema . substr($url, $pos);
+				$url = $scheme . substr($url, $pos);
 			}
 		}
 		return $url;
 	}
 
 	/**
-	 * Remembers URL passed
+	 * Remembers the specified URL so that it can be later fetched back.
 	 *
-	 * @param string $url URL to remember. Default is current URL.
-	 * @param string $name Name to use to remember URL. Defaults to `yii\web\User::returnUrlParam`.
+	 * @param string $url URL to remember. Default is the currently requested URL.
+	 * @param string $name Name to use to remember URL. Defaults to [[\yii\web\User::returnUrlParam]].
+	 * @see previous()
 	 */
 	public static function remember($url = '', $name = null)
 	{
@@ -164,10 +166,11 @@ class BaseUrl
 	}
 
 	/**
-	 * Returns URL previously saved with remember method
+	 * Returns the URL previously [[remember()|remembered]].
 	 *
-	 * @param string $name Name used to remember URL. Defaults to `yii\web\User::returnUrlParam`.
-	 * @return string URL
+	 * @param string $name Name used to remember URL. Defaults to [[\yii\web\User::returnUrlParam]].
+	 * @return string URL, or null if no such URL was remembered before.
+	 * @see remember()
 	 */
 	public static function previous($name = null)
 	{
@@ -198,23 +201,23 @@ class BaseUrl
 	}
 
 	/**
-	 * Returns home URL
+	 * Returns the home URL.
 	 *
-	 * @param boolean|string $schema URI schema to use:
+	 * @param boolean|string $scheme URI scheme to use:
 	 *
 	 * - `false`: relative URL. Default behavior.
 	 * - `true`: absolute URL with the current scheme.
-	 * - string: absolute URL with string value used as schema.
+	 * - string: absolute URL with string value used as scheme.
 	 *
 	 * @return string home URL
 	 */
-	public static function home($schema = false)
+	public static function home($scheme = false)
 	{
-		if ($schema) {
+		if ($scheme) {
 			$url = Yii::$app->getRequest()->getHostInfo() . Yii::$app->getHomeUrl();
-			if ($schema !== true) {
+			if ($scheme !== true) {
 				$pos = strpos($url, '://');
-				$url = $schema . substr($url, $pos);
+				$url = $scheme . substr($url, $pos);
 			}
 		} else {
 			$url = Yii::$app->getHomeUrl();
@@ -222,4 +225,3 @@ class BaseUrl
 		return $url;
 	}
 }
- 
\ No newline at end of file