Update README

README.md

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 # BasicAudioPlayer
 
-BasicAudioPlayer is an easy to customize AVAudioEngine-based player. It implements all the basic functions an audio player should have, so you can focus on adding AVAudioEngineNodes and custom features.
+BasicAudioPlayer is a library that makes it easier to create AVAudioEngine-based audio players.
 
 ## Installation
 
@@ -11,6 +11,95 @@ BasicAudioPlayer is a Swift package. To add it to your Xcode project:
   <li>Choose a dependency rule. "Up to Next Major Version" is the suggested setting.</li>
 </ol>
 
+## Getting Started
+
+### BAPlayer
+
+BAPlayer is an object that plays audio from a file. It features all the basic playback control methods an audio player should have, and lets you modulate its audio output by adding audio units to its effects chain. BAPlayer manages all of its audio nodes behind the hood, so you don't have to deal with that.
+
+#### Creating a BAPlayer
+
+Creating a new BAPlayer is straightforward. If you already know which audio file the player will play, you can load it at creation time using the appropriate initializer.
+
+```Swift
+// Create a player without loading an audio file
+let p = BAPlayer()
+
+// Create a player and load an audio file at a certain URL
+let audioFileURL = URL(fileURLWithPath: "/Some/Audio/file.m4a")
+let p1 = try BAPlayer(url: audioFileURL)
+
+// Create a player and load an audio file
+let audioFile = try AVAudioFile(forReading: audioFileURL)
+let p2 = BAPlayer(file: audioFile)
+```
+
+#### Loading an Audio File
+
+You can load an audio file after creating the player. A BAPlayer instance can handle the playback of only one audio file at a time. Therefore, if another file has already been loaded, it will be replaced with the new one.
+
+```Swift
+let player = BAPlayer()
+
+// Load an audio file at a certain URL
+let audioFileURL = URL(fileURLWithPath: "/Path/To/Audio/file.m4a")
+try player.load(url: audioFileURL)
+
+// Load an audio file
+let audioFile = try AVAudioFile(forReading: audioFileURL)
+player.load(file: audioFile)
+
+// Get the loaded audio file, if any
+let loadedFile: AVAudioFile? = player.file
+```
+
+#### Controlling Playback
+
+BAPlayer makes it easy to control audio playback. Here are the basic methods available.
+
+```Swift
+let player = BAPlayer(url: URL(fileURLWithPath: "/Some/Audio/file.m4a"))
+
+// Play audio
+player.play()
+
+// Pause audio
+player.pause()
+
+// Stop the playback and reset the elapsed time back to 0
+player.stop()
+```
+
+#### Handling Status Changes
+
+BAPlayer features a property named <code>status</code> that can be used to check what the player is doing. You can also provide a closure to execute when the player's status changes.
+
+```Swift
+let player = BAPlayer()
+
+// Get the status of the player
+let status = player.status
+
+// Add a closure to run when the player's status changes.
+player.onStatusChange { newStatus in
+    if newStatus == .playing {
+        print("The player is now playing")
+    }
+}
+```
+
+#### Adding Audio Units
+
+You can add audio units (<code>AVAudioUnit</code>) to a BAPlayer to manipulate its audio output. They will be connected in the order they were added.
+
+```Swift
+let player = BAPlayer()
+
+// Add a time pitch unit to the player's audio unit chain.
+let timePitchUnit = AVAudioUnitTimePitch()
+player.addAudioUnit(timePitchUnit)
+```
+
 ## License
 
 BasicAudioPlayer is available under the MIT license. See the LICENSE file for more info.