Update README.md

Author: sungshik

README.md

@@ -10,8 +10,11 @@ A Java file watcher that works across platforms and supports recursion, single f
 Features:
 
 - monitor a single file (or directory) for changes
-- monitor a directory for changes to its direct descendants
+- monitor a directory for changes to its direct children
 - monitor a directory for changes for all its descendants (aka recursive directory watch)
+- backends supported:
+  - the JDK [`WatchService`](https://docs.oracle.com/javase/8/docs/api/java/nio/file/WatchService.html) API on any platform
+  - the native [FSEvents](https://developer.apple.com/documentation/coreservices/file_system_events) API on macOS
 - edge cases dealt with:
   - recursive watches will also continue in new directories
   - multiple watches for the same directory are merged to avoid overloading the kernel
@@ -61,8 +64,8 @@ try(var active = watcherSetup.start()) {
 
 On all platforms except macOS, the library internally uses the JDK default implementation of the Java NIO [`WatchService`](https://docs.oracle.com/javase/8/docs/api/java/nio/file/WatchService.html) API.
 
-On macOS, the library internally uses our custom `WatchService` implementation based on macOS's native [file system event streams](https://developer.apple.com/documentation/coreservices/file_system_events?language=objc) (using JNA).
-Generally, it offers better performance than the JDK default implementation (because the latter uses a polling loop to detect changes only once every two seconds).
+On macOS, the library internally uses our custom `WatchService` implementation based on macOS's native [FSEvents](https://developer.apple.com/documentation/coreservices/file_system_events) API.
+Generally, it offers better performance than the JDK default implementation (because the latter uses a polling loop to detect changes at fixed time intervals).
 To force the library to use the JDK default implementation on macOS, set system property `engineering.swat.java-watch.mac` to `jdk`.
 
 ## Related work