README: add better explanation of the configurations

README.md

@@ -3,6 +3,23 @@ dnsmasq-china-list
 
 Configuration for hot China domains (or CDN domains that have node in China) to accelerate via Dnsmasq (Now also includes bogus-nxdomain lines to stop common DNS servers from hijacking NXDOMAIN results)
 
+Content
+=======
+
+- `accelerated-domains.china.conf`: Acceleratable Domains.
+
+  The domain should have a better resolving speed or result when using a Chinese DNS server.
+
+  To determine if a domain is eligible, one of the criteria below must be met:
+
+ - The domain's NS server is located in China.
+
+ - The domain will resolve to an IP located in China mainland when using a Chinese DNS server (For example, CDN accelerated sites that have node in China). This however does _not_ include those having node _near_ China mainland, like in Japan, Hong Kong, Taiwan, etc.
+ 
+  Please don't add subdomains if the top domain is already in the list. This includes all .cn domains which are already matched by the `/cn/` rule.
+
+- `bogus-nxdomain.china.conf`: Known addresses that are hijacking NXDOMAIN results returned by DNS servers.
+
 Usage
 =====