fix 309 (#566)
diff --git a/docs/docs/api/js-service.md b/docs/docs/api/js-service.md
index e8d30a6..818bbf7 100644
--- a/docs/docs/api/js-service.md
+++ b/docs/docs/api/js-service.md
@@ -11,7 +11,8 @@
<span class="weex-version">v0.9.5+</span>
-JSService and Weex instance are parallel in js runtime. Weex instance's lifecycle will invoke JSService's lifecycle. Currently provide create, refresh, destroy of lifecycle.
+JSService and Weex instance are parallel in js runtime. Weex instance's lifecycle will invoke JSService's lifecycle. Currently provide create, refresh, destroy of lifecycle.
+JSService is the same as vendor.js in front-end engineer world, it is usually used to move duplicated js function in each page to a global environment.
**!!!Important: Improper use of JSService may lead to increased memory usage or global pollution !**
diff --git a/docs/zh/docs/api/js-service.md b/docs/zh/docs/api/js-service.md
index 4be6958..59e4ff6 100644
--- a/docs/zh/docs/api/js-service.md
+++ b/docs/zh/docs/api/js-service.md
@@ -11,7 +11,8 @@
<span class="weex-version">v0.9.5+</span>
-JSService 和 Weex 实例在 JS Runtime 中并行运行。Weex 实例的生命周期可调用 JSService 生命周期。目前提供创建、刷新、销毁生命周期。
+JSService 和 Weex 实例在 JS Runtime 中并行运行。Weex 实例的生命周期可调用 JSService 生命周期。目前提供创建、刷新、销毁生命周期。
+JSService 和前端世界里的 vendor.js 一样，它通常用于将每个页面中的重复js函数移至全局环境。
**重要提醒: JSService 使用不当会导致内存增高或全局污染！**
