Update the category name

Metrics category and name needs to be optimized for the next version
diff --git a/README.md b/README.md
index 542c41b..0a85a84 100644
--- a/README.md
+++ b/README.md
@@ -17,9 +17,9 @@
 	-   [Run Docker Image](#run-docker-image)
 -   [Metrics](#metrics)
 	-   [Broker](#broker)
-	-   [Topics](#topics)
+	-   [Producer](#producer)
 	-   [Consumer Groups](#consumer-groups)
-	-   [RocketMQ Client](#RocketMQ Client)
+	-   [Consumer](#consumer)
 -   [Grafana Dashboard](#grafana-dashboard)
 -   [Quick Start](#quick-start)
 
@@ -100,7 +100,7 @@
 rocketmq_broker_qps{cluster="MQCluster",broker="broker-b",} 8.0
 ```
 
-### Topics
+### Producer
 
 **Metrics details**
 
@@ -204,7 +204,7 @@
 rocketmq_group_get_latency_by_storetime{cluster="MQCluster",broker="broker-b",topic="DEV_TID_tfq",group="DEV_CID_cfq",} 0.0
 ```
 
-### RocketMQ Client
+### Consumer
 
 **Metrics details**