diff --git a/README.md b/README.md
index 8c4e63f..6c054d1 100644
--- a/README.md
+++ b/README.md
@@ -6,8 +6,8 @@ This is an rMQR Code image generator implemented in Python. This is implemented
 
 
 ## 📌 Important Notice
-Please verify an image generated by this software whether it can decode correctly before use.
-
+- Please verify an image generated by this software whether it can decode correctly before use.
+- Because this is in early stage, QR Code readers may have not been supported rMQR Code yet.
 
 ## 🚀 Installation
 ```
diff --git a/setup.cfg b/setup.cfg
index bdb177a..ada13c1 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,6 +1,6 @@
 [metadata]
 name = rmqrcode
-version = 0.1.2
+version = 0.1.3
 author = Takahiro Tomita
 author_email = ttp8101@gmail.com
 description = An rMQR Code Generetor
diff --git a/src/rmqrcode/console.py b/src/rmqrcode/console.py
index 8e0324d..aa1117e 100644
--- a/src/rmqrcode/console.py
+++ b/src/rmqrcode/console.py
@@ -53,17 +53,18 @@ def main():
     elif args.fit_strategy == 'min_height':
         fit_strategy = FitStrategy.MINIMIZE_HEIGHT
 
-    qr = _make_qr(
-        args.DATA,
-        ecc=ecc,
-        version=args.version,
-        fit_strategy=fit_strategy
-    )
+    try:
+        qr = _make_qr(
+            args.DATA,
+            ecc=ecc,
+            version=args.version,
+            fit_strategy=fit_strategy
+        )
+    except DataTooLongError:
+        _show_error_and_exit("Error: The data is too long.")
 
     _save_image(qr, args.OUTPUT)
 
-    print(f"{qr}")
-
 
 def _init_argparser():
     parser = argparse.ArgumentParser()
diff --git a/src/rmqrcode/format/data_capacities.py b/src/rmqrcode/format/data_capacities.py
index 7cb8541..58b3739 100644
--- a/src/rmqrcode/format/data_capacities.py
+++ b/src/rmqrcode/format/data_capacities.py
@@ -2,7 +2,7 @@
 
 
 # ISO/IEC 23941:2022 Table 6
-data_capacities = {
+DataCapacities = {
     'R7x43': {
         'height': 7,
         'width': 43,
diff --git a/src/rmqrcode/format/qr_versions.py b/src/rmqrcode/format/rmqr_versions.py
similarity index 99%
rename from src/rmqrcode/format/qr_versions.py
rename to src/rmqrcode/format/rmqr_versions.py
index 1c29e8a..2bc9232 100644
--- a/src/rmqrcode/format/qr_versions.py
+++ b/src/rmqrcode/format/rmqr_versions.py
@@ -1,7 +1,7 @@
 from .error_correction_level import ErrorCorrectionLevel
 
 
-qr_versions = {
+rMQRVersions = {
     'R7x43': {
         'version_indicator': 0b00000,
         'height': 7,
diff --git a/src/rmqrcode/rmqrcode.py b/src/rmqrcode/rmqrcode.py
index 87ab1c2..466934b 100644
--- a/src/rmqrcode/rmqrcode.py
+++ b/src/rmqrcode/rmqrcode.py
@@ -1,6 +1,6 @@
 from .format.error_correction_level import ErrorCorrectionLevel
-from .format.qr_versions import qr_versions
-from .format.data_capacities import data_capacities
+from .format.rmqr_versions import rMQRVersions
+from .format.data_capacities import DataCapacities
 from .format.alignment_pattern_coordinates import AlignmentPatternCoordinates
 from .format.generator_polynomials import GeneratorPolynomials
 from .format.mask import mask
@@ -33,7 +33,7 @@ def fit(data,ecc=ErrorCorrectionLevel.M, fit_strategy=FitStrategy.BALANCED):
         determined_height = set()
 
         logger.debug("Select rMQR Code version")
-        for version_name, qr_version in data_capacities.items():
+        for version_name, qr_version in DataCapacities.items():
             if data_length <= qr_version['capacity']['Byte'][ecc]:
                 width, height = qr_version['width'], qr_version['height']
                 if not width in determined_width and not height in determined_height:
@@ -69,7 +69,7 @@ def __init__(self, version, ecc, logger=None):
         if not rMQR.validate_version(version):
             raise IllegalVersionError("The rMQR version is illegal.")
 
-        qr_version = qr_versions[version]
+        qr_version = rMQRVersions[version]
         self._version = version
         self._height = qr_version['height']
         self._width = qr_version['width']
@@ -134,7 +134,7 @@ def __str__(self):
 
     def _put_finder_pattern(self):
         # Finder pattern
-        # 周囲
+        # Outer square
         for i in range(7):
             for j in range(7):
                 if i == 0 or i == 6 or j == 0 or j == 6:
@@ -142,7 +142,7 @@ def _put_finder_pattern(self):
                 else:
                     self._qr[i][j] = Color.WHITE
 
-        # 真ん中
+        # Inner square
         for i in range(3):
             for j in range(3):
                 self._qr[2+i][2+j] = Color.BLACK
@@ -156,19 +156,19 @@ def _put_finder_pattern(self):
                 self._qr[7][n] = Color.WHITE
 
         # Finder sub pattern
-        # 周囲
+        # Outer square
         for i in range(5):
             for j in range(5):
                 color = Color.BLACK if i == 0 or i == 4 or j == 0 or j == 4 else Color.WHITE
                 self._qr[self._height-i-1][self._width-j-1] = color
 
-        # 真ん中
+        # Inner square
         self._qr[self._height-1-2][self._width-1-2] = Color.BLACK
 
 
     def _put_corner_finder_pattern(self):
         # Corner finder pattern
-        # 左下
+        # Bottom left
         self._qr[self._height-1][0] = Color.BLACK
         self._qr[self._height-1][1] = Color.BLACK
         self._qr[self._height-1][2] = Color.BLACK
@@ -177,7 +177,7 @@ def _put_corner_finder_pattern(self):
             self._qr[self._height-2][0] = Color.BLACK
             self._qr[self._height-2][1] = Color.WHITE
 
-        # 右上
+        # Top right
         self._qr[0][self._width-1] = Color.BLACK
         self._qr[0][self._width-2] = Color.BLACK
         self._qr[1][self._width-1] = Color.BLACK
@@ -191,22 +191,22 @@ def _put_alignment_pattern(self):
             for i in range(3):
                 for j in range(3):
                     color = Color.BLACK if i == 0 or i == 2 or j == 0 or j == 2 else Color.WHITE
-                    # 上側
+                    # Top side
                     self._qr[i][center_x + j - 1] = color
-                    # 下側
+                    # Bottom side
                     self._qr[self._height-1-i][center_x + j - 1] = color
 
 
     def _put_timing_pattern(self):
         # Timing pattern
-        # 横
+        # Horizontal
         for j in range(self._width):
             color = Color.BLACK if (j + 1) % 2 else Color.WHITE
             for i in [0, self._height - 1]:
                 if self._qr[i][j] == Color.UNDEFINED:
                     self._qr[i][j] = color
 
-        # 縦
+        # Vertical
         center_xs = [0, self._width - 1]
         center_xs.extend(AlignmentPatternCoordinates[self._width])
         for i in range(self._height):
@@ -248,7 +248,7 @@ def _put_version_information_finder_sub_pattern_side(self, version_information):
 
 
     def _compute_version_info(self):
-        qr_version = qr_versions[self.version_name()]
+        qr_version = rMQRVersions[self.version_name()]
         version_information_data = qr_version['version_indicator']
         if self._error_correction_level == ErrorCorrectionLevel.H:
             version_information_data |= 1<<6
@@ -258,14 +258,17 @@ def _compute_version_info(self):
 
 
     def _put_data(self, data):
-        qr_version = qr_versions[self.version_name()]
+        qr_version = rMQRVersions[self.version_name()]
 
         character_count_length = qr_version['character_count_length']
         codewords_total = qr_version['codewords_total']
         encoded_data = self._convert_to_bites_data(data, character_count_length, codewords_total)
         codewords = split_into_8bits(encoded_data)
 
-        # codeword数に満たない場合は規定の文字列を付与する
+        if len(codewords) > codewords_total:
+            raise DataTooLongError("The data is too long.")
+
+        # Add the remainder codewords
         while True:
             if len(codewords) >= codewords_total:
                 break
@@ -279,7 +282,7 @@ def _put_data(self, data):
             qr_version['blocks'][self._error_correction_level]
         )
 
-        # データの並び替え
+        # Construct the final message codeword sequence
         # Data codewords
         final_codewords = []
         for i in range(len(data_codewords_per_block[-1])):
@@ -297,8 +300,8 @@ def _put_data(self, data):
                 final_codewords.append(rs_codewords[i])
                 self._logger.debug(f"Put RS data codewords {i} : {rs_codewords[i]}")
 
-        # 配置
-        dy = -1 # 最初は上方向
+        # Codeword placement
+        dy = -1 # Up
         current_codeword_idx = 0
         current_bit_idx = 0
         cx, cy = self._width - 2, self._height - 6
@@ -308,14 +311,14 @@ def _put_data(self, data):
         while True:
             for x in [cx, cx-1]:
                 if self._qr[cy][x] == Color.UNDEFINED:
-                    # 空白のセルのみ処理する
+                    # Process only empty cell
                     if current_codeword_idx == len(final_codewords):
-                        # codewordsを配置しきった場合はremainder_bitsがあれば配置する
+                        # Remainder bits
                         self._qr[cy][x] = Color.WHITE
                         mask_area[cy][x] = True
                         remainder_bits -= 1
                     else:
-                        # codewordsを配置する
+                        # Codewords
                         self._qr[cy][x] = Color.BLACK if final_codewords[current_codeword_idx][current_bit_idx] == '1' else Color.WHITE
                         mask_area[cy][x] = True
                         current_bit_idx += 1
@@ -323,15 +326,13 @@ def _put_data(self, data):
                             current_bit_idx = 0
                             current_codeword_idx += 1
 
-                    # codewordsの配置が終わりremainder_bitsも残っていなければ終了
                     if current_codeword_idx == len(final_codewords) and remainder_bits == 0:
                         break
 
-            # codewordsの配置が終わりremainder_bitsも残っていなければ終了
             if current_codeword_idx == len(final_codewords) and remainder_bits == 0:
                 break
 
-            # 座標の更新
+            # Update current coordinates
             if dy < 0 and cy == 1:
                 cx -= 2
                 dy = 1
@@ -369,7 +370,7 @@ def _split_into_blocks(self, codewords, blocks_definition):
     def _convert_to_bites_data(self, data, character_count_length, codewords_total):
         encoded_data = ByteEncoder.encode(data, character_count_length)
 
-        # 付加できるなら終端文字を付け加える
+        # Terminator (may be truncated)
         if len(encoded_data) + 3 <= codewords_total * 8:
             encoded_data += "000"
 
@@ -390,7 +391,7 @@ def _apply_mask(self, mask_area):
 
     @staticmethod
     def validate_version(version_name):
-        return version_name in qr_versions
+        return version_name in rMQRVersions
 
 
 class DataTooLongError(ValueError):
diff --git a/src/rmqrcode/util/galois_fields.py b/src/rmqrcode/util/galois_fields.py
index c23e210..6b3c076 100644
--- a/src/rmqrcode/util/galois_fields.py
+++ b/src/rmqrcode/util/galois_fields.py
@@ -4,7 +4,7 @@ class GaloisFields:
     i2e = {}
 
     def __init__(self):
-        # GF(2^8)の既約多項式
+        # Irreducible polynomial in GF(2^8)
         p = (1<<8)|(1<<4)|(1<<3)|(1<<2)|1
 
         self.e2i[0] = 1