diff --git a/docs/configuration.md b/docs/configuration.md
index 340bfd96..0817a8ca 100644
--- a/docs/configuration.md
+++ b/docs/configuration.md
@@ -73,10 +73,10 @@ When WebP support detection is enabled, please take care to configure your CDN o
 
 ### Watermark
 
-* `IMGPROXY_WATERMARK_DATA` - Base64-encoded image data. You can easily calculate it with `base64 tmp/watermark.png | tr -d '\n'`;
-* `IMGPROXY_WATERMARK_PATH` - path to the locally stored image;
-* `IMGPROXY_WATERMARK_URL` - watermark image URL;
-* `IMGPROXY_WATERMARK_OPACITY` - watermark base opacity.
+* `IMGPROXY_WATERMARK_DATA`: Base64-encoded image data. You can easily calculate it with `base64 tmp/watermark.png | tr -d '\n'`;
+* `IMGPROXY_WATERMARK_PATH`: path to the locally stored image;
+* `IMGPROXY_WATERMARK_URL`: watermark image URL;
+* `IMGPROXY_WATERMARK_OPACITY`: watermark base opacity.
 
 Read more about watermarks in the [Watermark](./watermark.md) guide.
 
@@ -136,8 +136,8 @@ Check out the [Serving files from Google Cloud Storage](./serving_files_from_goo
 
 imgproxy can send its metrics to New Relic. Specify your New Relic license key to activate this feature:
 
-* `IMGPROXY_NEW_RELIC_KEY` - New Relic license key;
-* `IMGPROXY_NEW_RELIC_APP_NAME` - application name. If not specified, `imgproxy` will be used as the application name.
+* `IMGPROXY_NEW_RELIC_KEY`: New Relic license key;
+* `IMGPROXY_NEW_RELIC_APP_NAME`: application name. If not specified, `imgproxy` will be used as the application name.
 
 Check out the [New Relic](./new_relic.md) guide to learn more.
 
diff --git a/docs/generating_the_url_advanced.md b/docs/generating_the_url_advanced.md
index 0040411b..2afa070b 100644
--- a/docs/generating_the_url_advanced.md
+++ b/docs/generating_the_url_advanced.md
@@ -241,15 +241,33 @@ There are two ways to specify source url:
 
 ##### Plain
 
-The source URL can be provided as is forwarded by `/plain/` part. If the sorce URL contains query string or `@`, you need to escape it.
+The source URL can be provided as is, prendended by `/plain/` part:
 
-When using plain source URL, you can specify the [extension](#extension) after `@`.
+```
+/plain/http://example.com/images/curiosity.jpg
+```
+
+**Note:** If the sorce URL contains query string or `@`, you need to escape it.
+
+When using plain source URL, you can specify the [extension](#extension) after `@`:
+
+```
+/plain/http://example.com/images/curiosity.jpg@png
+```
 
 ##### Base64 encoded
 
-The source URL can be encoded with URL-safe Base64. The encoded URL can be split with `/` for your needs.
+The source URL can be encoded with URL-safe Base64. The encoded URL can be split with `/` for your needs:
 
-When using encoded source URL, you can specify the [extension](#extension) after `.`.
+```
+/aHR0cDovL2V4YW1w/bGUuY29tL2ltYWdl/cy9jdXJpb3NpdHku/anBn
+```
+
+When using encoded source URL, you can specify the [extension](#extension) after `.`:
+
+```
+/aHR0cDovL2V4YW1w/bGUuY29tL2ltYWdl/cy9jdXJpb3NpdHku/anBn.png
+```
 
 #### Extension
 
diff --git a/docs/generating_the_url_basic.md b/docs/generating_the_url_basic.md
index 7648b3fd..7e22d500 100644
--- a/docs/generating_the_url_basic.md
+++ b/docs/generating_the_url_basic.md
@@ -57,15 +57,33 @@ There are two ways to specify source url:
 
 ##### Plain
 
-The source URL can be provided as is forwarded by `/plain/` part. If the sorce URL contains query string or `@`, you need to escape it.
+The source URL can be provided as is, prendended by `/plain/` part:
 
-When using plain source URL, you can specify the [extension](#extension) after `@`.
+```
+/plain/http://example.com/images/curiosity.jpg
+```
+
+**Note:** If the sorce URL contains query string or `@`, you need to escape it.
+
+When using plain source URL, you can specify the [extension](#extension) after `@`:
+
+```
+/plain/http://example.com/images/curiosity.jpg@png
+```
 
 ##### Base64 encoded
 
-The source URL can be encoded with URL-safe Base64. The encoded URL can be split with `/` for your needs.
+The source URL can be encoded with URL-safe Base64. The encoded URL can be split with `/` for your needs:
 
-When using encoded source URL, you can specify the [extension](#extension) after `.`.
+```
+/aHR0cDovL2V4YW1w/bGUuY29tL2ltYWdl/cy9jdXJpb3NpdHku/anBn
+```
+
+When using encoded source URL, you can specify the [extension](#extension) after `.`:
+
+```
+/aHR0cDovL2V4YW1w/bGUuY29tL2ltYWdl/cy9jdXJpb3NpdHku/anBn.png
+```
 
 #### Extension