diff --git a/data.c b/data.c
new file mode 100644
index 0000000..e16572a
--- /dev/null
+++ b/data.c
@@ -0,0 +1,229 @@
+#include "Data.h"
+#include <Memory.h>
+#include "fast.memory.h"
+
+typedef union _Data {
+    LongWord size;
+    char data[4];
+} _Data;
+
+#define SIZEOF_DATA_HEADER sizeof(LongWord);
+
+#define H_TO_D(h) *((_Data **)h)
+
+static Boolean reserve(Handle h, LongWord size)
+{
+    //LongWord currentSize;
+    //currentSize = _GetHandleSize(h);
+    
+    // size includes the data header.
+        
+    size = (size + 4095) & ~4095;
+    
+    //if (size <= currentSize) return true;
+    _HUnlock(h);
+    
+    SetHandleSize(size, h);
+    if (_toolErr) return 0;
+    _HLock(h);
+    
+    return 1;
+}
+
+/*
+ * Create a Data Handle.
+ *
+ */
+Handle DataCreate(Word MemID, Word initialSize)
+{
+    Handle h;
+    
+    if (initialSize < 1024) initialSize = 1024;
+    
+    h = NewHandle(initialSize, MemID, attrNoSpec | attrLocked, NULL);
+    if (_toolErr) return NULL;
+
+    (H_TO_D(h))->size = SIZEOF_DATA_HEADER;
+    return h;
+}
+
+
+/*
+ * reset the size to 0.
+ *
+ */
+Word DataReset(Handle h)
+{
+    if (!h) return 0;
+    
+    _HLock(h);
+    (H_TO_D(h))->size = SIZEOF_DATA_HEADER;
+    _HUnlock(h);
+    
+    return 1;
+}
+
+
+Word DataAppendPString(Handle h, const char *s)
+{
+    if (!h) return 0;
+    if (!s || !*s) return 1;
+    
+    return DataAppendBytes(h, s + 1, *s);
+}
+
+Word DataAppendGSString(Handle h, const GSString255Ptr s)
+{
+    if (!h) return 0;    
+    if (!s || !s->length) return 1;
+    
+    return DataAppendBytes(h, s->text, s->length);
+}
+
+Word DataAppendCString(Handle h, const char *cp)
+{
+    Word l;
+
+    if (!h) return 0;
+    
+    if (!cp || !*cp) return 1;
+
+    // strlen (cp)
+    /*
+     * xba - sets Z if (A & 0x00ff) == 0
+     */
+     //
+    asm {
+        ldy #0
+    loop:
+        lda [<cp],y
+        xba // a = byte 0
+        beq done
+        iny
+        xba // a = byte 1
+        beq done
+        iny
+        bne loop    // not bra in case not terminated
+    done:
+        sty <l
+    }
+
+    return DataAppendBytes(h, cp, l);
+}
+
+
+Word DataAppendBytes(Handle h, const char *bytes, LongWord count)
+{
+    _Data *data;
+    LongWord dSize;
+    LongWord hSize;
+    LongWord newSize; 
+    
+    if (!h) return 0;
+    
+    _HLock(h);
+    
+    data = H_TO_D(h);
+    dSize = data->size;
+    hSize = _GetHandleSize(h);
+    
+    newSize = dSize + count;
+    if (newSize > hSize)
+    {
+        if (!reserve(h, newSize)) return 0;
+        data = H_TO_D(h);    
+    }    
+    
+    BlockMove(bytes, data->data + dSize, count);
+    
+    data->size = newSize;
+    return 1;
+}
+
+Word DataAppendChar(Handle h, char c)
+{
+    _Data *data;
+    LongWord dSize;
+    LongWord hSize;
+    LongWord newSize;
+
+    if (!h) return 0;
+
+    _HLock(h);
+
+    data = H_TO_D(h);
+    dSize = data->size;
+    hSize = _GetHandleSize(h);
+
+    newSize = dSize + 1; // dSize includes header.
+    
+    if (newSize > hSize)
+    {
+        if (!reserve(h, newSize)) return 0;
+        data = H_TO_D(h);    
+    }
+    
+    data->data[dSize] = c;
+    data->size = newSize;
+
+    return 1;
+}
+
+
+LongWord DataSize(Handle h)
+{
+    if (!h) return 0;
+    return (H_TO_D(h))->size - SIZEOF_DATA_HEADER;
+}
+
+void *DataBytes(Handle h)
+{
+    _Data *data;
+    
+    if (!h) return NULL;
+    
+    _HLock(h);
+    
+    data = H_TO_D(h);
+    return data->data + SIZEOF_DATA_HEADER;
+}
+
+/*
+ * guarantee at least minSize bytes available and
+ * return a raw pointer to the data.
+ */
+char *DataLock(Handle h, Word newSize)
+{
+    LongWord hSize;
+    _Data *data;
+    
+    if (!h) return NULL;
+    
+    _HLock(h);
+  
+      if (newSize)
+      {  
+        newSize += SIZEOF_DATA_HEADER;
+        
+        hSize = _GetHandleSize(h);
+        
+        if (newSize > hSize)
+        {
+            if (!reserve(h, newSize)) return NULL;
+            
+            // should also bzero it?
+        }
+    }
+    
+    data = H_TO_D(h);
+    return data->data + SIZEOF_DATA_HEADER;
+}
+
+void DataUnlock(Handle h, Word newSize)
+{
+    if (!h) return;
+    
+    if (newSize == -1) return;
+    
+    (H_TO_D(h))->size = newSize + SIZEOF_DATA_HEADER;
+}
diff --git a/data.h b/data.h
new file mode 100644
index 0000000..51e506a
--- /dev/null
+++ b/data.h
@@ -0,0 +1,23 @@
+#ifndef __DATA_H__
+#define __DATA_H__
+
+#include <Types.h>
+
+Handle DataCreate(Word MemID, Word initialSize);
+Word DataReset(Handle h);
+
+Word DataAppendChar(Handle h, char c);
+
+Word DataAppendBytes(Handle h, const char *data, LongWord count);
+
+Word DataAppendCString(Handle h, const char *s);
+Word DataAppendPString(Handle h, const char *s);
+Word DataAppendGSString(Handle h, const GSString255Ptr s);
+
+LongWord DataSize(Handle h);
+void *DataBytes(Handle h);
+
+char *DataLock(Handle h, Word minSize);
+void DataUnlock(Handle h, Word newSize);
+
+#endif