diff --git a/common/JackAudioDriver.cpp b/common/JackAudioDriver.cpp
index cc3de2c5..52ab00a8 100644
--- a/common/JackAudioDriver.cpp
+++ b/common/JackAudioDriver.cpp
@@ -203,7 +203,7 @@ int JackAudioDriver::Process()
 }
 
 /*
-The driver ASYNC mode: output buffers computed at the *previous cycle* are used, the server does not
+The driver "asynchronous" mode: output buffers computed at the *previous cycle* are used, the server does not
 synchronize to the end of client graph execution.
 */
 
@@ -239,6 +239,10 @@ void JackAudioDriver::ProcessGraphAsync()
     }
 }
 
+/*
+Used when the driver works in master mode.
+*/
+
 void JackAudioDriver::ProcessGraphAsyncMaster()
 {
     // fBeginDateUst is set in the "low level" layer, fEndDateUst is from previous cycle
@@ -261,6 +265,10 @@ void JackAudioDriver::ProcessGraphAsyncMaster()
     // Does not wait on graph execution end
 }
 
+/*
+Used when the driver works in slave mode.
+*/
+
 void JackAudioDriver::ProcessGraphAsyncSlave()
 {
     if (ResumeRefNum() < 0) {
@@ -269,7 +277,7 @@ void JackAudioDriver::ProcessGraphAsyncSlave()
 }
 
 /*
-The driver SYNC mode: the server does synchronize to the end of client graph execution,
+The driver "synchronous" mode: the server does synchronize to the end of client graph execution,
 if graph process succeed, output buffers computed at the *current cycle* are used.
 */
 
@@ -305,6 +313,10 @@ void JackAudioDriver::ProcessGraphSync()
     }
 }
 
+/*
+Used when the driver works in master mode.
+*/
+
 void JackAudioDriver::ProcessGraphSyncMaster()
 {
     // fBeginDateUst is set in the "low level" layer, fEndDateUst is from previous cycle
@@ -332,6 +344,10 @@ void JackAudioDriver::ProcessGraphSyncMaster()
     }
 }
 
+/*
+Used when the driver works in slave mode.
+*/
+
 void JackAudioDriver::ProcessGraphSyncSlave()
 {
     if (ResumeRefNum() < 0) {
diff --git a/common/JackAudioDriver.h b/common/JackAudioDriver.h
index d6edd0c4..e6f332f0 100644
--- a/common/JackAudioDriver.h
+++ b/common/JackAudioDriver.h
@@ -28,6 +28,15 @@ namespace Jack
 
 /*!
 \brief The base class for audio drivers: drivers with audio ports.
+
+A concrete derived class will have to be defined with a real audio driver API, 
+either callback based one (like CoreAudio, PortAudio..) ones or blocking ones (like ALSA).
+
+Most of the generic audio handing code is part of this class :
+    - concrete callback basedd derived subclasses typically have to Open/Close the underlying audio API, 
+        setup the audio callback and implement the Read/Write methods
+    - concrete blocking based derived subclasses typically have to Open/Close the underlying audio API, 
+        implement the Read/Write methods and "wraps" the driver with the JackThreadDriver class.
 */
 
 class SERVER_EXPORT JackAudioDriver : public JackDriver
@@ -69,6 +78,10 @@ class SERVER_EXPORT JackAudioDriver : public JackDriver
                         jack_nframes_t capture_latency,
                         jack_nframes_t playback_latency);
 
+        /*
+            To be called by the underlying driver audio callback, or possibly by a RT thread (using JackThreadedDriver decorator) 
+            when a blocking read/write underlying API is used (like ALSA)
+        */
         virtual int Process();
 
         virtual int Attach();
diff --git a/common/JackDriver.h b/common/JackDriver.h
index 772ce1f2..804d9b27 100644
--- a/common/JackDriver.h
+++ b/common/JackDriver.h
@@ -95,9 +95,11 @@ class SERVER_EXPORT JackDriverInterface
         virtual int ProcessRead() = 0;
         virtual int ProcessWrite() = 0;
 
+        // For "slave" driver in "synchronous" mode
         virtual int ProcessReadSync() = 0;
         virtual int ProcessWriteSync() = 0;
 
+        // For "slave" driver in "asynchronous" mode
         virtual int ProcessReadAsync() = 0;
         virtual int ProcessWriteAsync() = 0;
 
@@ -231,15 +233,17 @@ class SERVER_EXPORT JackDriver : public JackDriverClientInterface
         int ProcessReadSlaves();
         int ProcessWriteSlaves();
 
-        // For "slave" driver
-        int ProcessRead();
-        int ProcessWrite();
+        // For "slave" driver with typically decompose a given cycle in separated Read and Write parts.
+        virtual int ProcessRead();
+        virtual int ProcessWrite();
 
-        int ProcessReadSync();
-        int ProcessWriteSync();
+        // For "slave" driver in "synchronous" mode
+        virtual int ProcessReadSync();
+        virtual int ProcessWriteSync();
 
-        int ProcessReadAsync();
-        int ProcessWriteAsync();
+        // For "slave" driver in "asynchronous" mode
+        virtual int ProcessReadAsync();
+        virtual int ProcessWriteAsync();
 
         virtual bool IsFixedBufferSize();
         virtual int SetBufferSize(jack_nframes_t buffer_size);
diff --git a/common/JackMidiDriver.h b/common/JackMidiDriver.h
index 204d6bbf..76f187db 100644
--- a/common/JackMidiDriver.h
+++ b/common/JackMidiDriver.h
@@ -30,6 +30,10 @@ namespace Jack
 
 /*!
 \brief The base class for MIDI drivers: drivers with MIDI ports.
+
+A concrete derived class will have to be defined with a real MIDI driver API, 
+either callback based one (like CoreMIDI..) ones or blocking ones (like ALSA MIDI).
+
 */
 
 class SERVER_EXPORT JackMidiDriver : public JackDriver