diff --git a/src/mnemonics/electrum-words.cpp b/src/mnemonics/electrum-words.cpp
index e644e0cbf..053941194 100644
--- a/src/mnemonics/electrum-words.cpp
+++ b/src/mnemonics/electrum-words.cpp
@@ -95,14 +95,13 @@ namespace
           it->substr(0, Language::unique_prefix_length) : *it);
       }
     }
-    std::unordered_map<std::string, uint32_t> word_map;
-    std::unordered_map<std::string, uint32_t> trimmed_word_map;
+
     // Iterate through all the languages and find a match
     for (std::vector<Language::Base*>::iterator it1 = language_instances.begin();
       it1 != language_instances.end(); it1++)
     {
-      word_map = (*it1)->get_word_map();
-      trimmed_word_map = (*it1)->get_trimmed_word_map();
+      std::unordered_map<std::string, uint32_t> &word_map = (*it1)->get_word_map();
+      std::unordered_map<std::string, uint32_t> &trimmed_word_map = (*it1)->get_trimmed_word_map();
       // To iterate through seed words
       std::vector<std::string>::const_iterator it2;
       // To iterate through trimmed seed words
@@ -285,7 +284,6 @@ namespace crypto
 
       if (sizeof(src.data) % 4 != 0 || sizeof(src.data) == 0) return false;
 
-      std::vector<std::string> word_list;
       Language::Base *language;
       if (language_name == "English")
       {
@@ -307,7 +305,7 @@ namespace crypto
       {
         return false;
       }
-      word_list = language->get_word_list();
+      std::vector<std::string> &word_list = language->get_word_list();
       // To store the words for random access to add the checksum word later.
       std::vector<std::string> words_store;
 
diff --git a/src/mnemonics/electrum-words.h b/src/mnemonics/electrum-words.h
index 1535fff1b..3be4b1ccc 100644
--- a/src/mnemonics/electrum-words.h
+++ b/src/mnemonics/electrum-words.h
@@ -81,7 +81,7 @@ namespace crypto
 
     /*!
      * \brief Gets a list of seed languages that are supported.
-     * \param languages The vector is set to the list of languages.
+     * \param languages A vector is set to the list of languages.
      */
     void get_language_list(std::vector<std::string> &languages);
 
diff --git a/src/mnemonics/english.h b/src/mnemonics/english.h
index ee2e248d9..e596f7b03 100644
--- a/src/mnemonics/english.h
+++ b/src/mnemonics/english.h
@@ -27,6 +27,12 @@
 // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
 // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+/*!
+ * \file english.h
+ * 
+ * \brief English word list and map.
+ */
+
 #ifndef ENGLISH_H
 #define ENGLISH_H
 
@@ -35,6 +41,10 @@
 #include "language_base.h"
 #include <string>
 
+/*!
+ * \namespace Language
+ * \brief Mnemonic language related namespace.
+ */
 namespace Language
 {
 	class English: public Base
diff --git a/src/mnemonics/japanese.h b/src/mnemonics/japanese.h
index 1c53a808e..2e77aa257 100644
--- a/src/mnemonics/japanese.h
+++ b/src/mnemonics/japanese.h
@@ -27,6 +27,12 @@
 // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
 // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+/*!
+ * \file japanese.h
+ * 
+ * \brief Japanese word list and map.
+ */
+
 #ifndef JAPANESE_H
 #define JAPANESE_H
 
@@ -35,6 +41,10 @@
 #include "language_base.h"
 #include <string>
 
+/*!
+ * \namespace Language
+ * \brief Mnemonic language related namespace.
+ */
 namespace Language
 {
 	class Japanese: public Base
diff --git a/src/mnemonics/language_base.h b/src/mnemonics/language_base.h
index b8b6a162f..1d08095d7 100644
--- a/src/mnemonics/language_base.h
+++ b/src/mnemonics/language_base.h
@@ -1,3 +1,9 @@
+/*!
+ * \file language_base.h
+ * 
+ * \brief Language Base class for Polymorphism.
+ */
+
 #ifndef LANGUAGE_BASE_H
 #define LANGUAGE_BASE_H
 
@@ -5,16 +11,28 @@
 #include <unordered_map>
 #include <string>
 
+/*!
+ * \namespace Language
+ * \brief Mnemonic language related namespace.
+ */
 namespace Language
 {
-	const int unique_prefix_length = 4;
+	const int unique_prefix_length = 4; /*!< Length of the prefix of all words guaranteed to be unique */
+	/*!
+	 * \class Base
+	 * \brief A base language class which all languages have to inherit from for
+	 * Polymorphism.
+	 */
 	class Base
 	{
 	protected:
-		std::vector<std::string> *word_list;
-		std::unordered_map<std::string, uint32_t> *word_map;
-		std::unordered_map<std::string, uint32_t> *trimmed_word_map;
-		std::string language_name;
+		std::vector<std::string> *word_list; /*!< A pointer to the array of words */
+		std::unordered_map<std::string, uint32_t> *word_map; /*!< hash table to find word's index */
+		std::unordered_map<std::string, uint32_t> *trimmed_word_map; /*!< hash table to find word's trimmed index */
+		std::string language_name; /*!< Name of language */
+		/*!
+		 * \brief Populates the word maps after the list is ready.
+		 */
 		void populate_maps()
 		{
 			int ii;
@@ -22,9 +40,9 @@ namespace Language
 			for (it = word_list->begin(), ii = 0; it != word_list->end(); it++, ii++)
 			{
 				(*word_map)[*it] = ii;
-				if (it->length() > 4)
+				if (it->length() > unique_prefix_length)
 				{
-					(*trimmed_word_map)[it->substr(0, 4)] = ii;
+					(*trimmed_word_map)[it->substr(0, unique_prefix_length)] = ii;
 				}
 				else
 				{
@@ -39,18 +57,34 @@ namespace Language
 			word_map = new std::unordered_map<std::string, uint32_t>;
 			trimmed_word_map = new std::unordered_map<std::string, uint32_t>;
 		}
+		/*!
+		 * \brief Returns a pointer to the word list.
+		 * \return A pointer to the word list.
+		 */
 		const std::vector<std::string>& get_word_list() const
 		{
 			return *word_list;
 		}
+		/*!
+		 * \brief Returns a pointer to the word map.
+		 * \return A pointer to the word map.
+		 */
 		const std::unordered_map<std::string, uint32_t>& get_word_map() const
 		{
 			return *word_map;
 		}
+		/*!
+		 * \brief Returns a pointer to the trimmed word map.
+		 * \return A pointer to the trimmed word map.
+		 */
 		const std::unordered_map<std::string, uint32_t>& get_trimmed_word_map() const
 		{
 			return *trimmed_word_map;
 		}
+		/*!
+		 * \brief Returns the name of the language.
+		 * \return Name of the language.
+		 */
 		std::string get_language_name() const
 		{
 			return language_name;
diff --git a/src/mnemonics/old_english.h b/src/mnemonics/old_english.h
index 4e40b1730..21772cdc3 100644
--- a/src/mnemonics/old_english.h
+++ b/src/mnemonics/old_english.h
@@ -27,6 +27,12 @@
 // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
 // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+/*!
+ * \file old_english.h
+ * 
+ * \brief Old English word list and map.
+ */
+
 #ifndef OLD_ENGLISH_H
 #define OLD_ENGLISH_H
 
@@ -35,6 +41,10 @@
 #include "language_base.h"
 #include <string>
 
+/*!
+ * \namespace Language
+ * \brief Mnemonic language related namespace.
+ */
 namespace Language
 {
 	class OldEnglish: public Base
diff --git a/src/mnemonics/portuguese.h b/src/mnemonics/portuguese.h
index 06d53f176..5b88a0686 100644
--- a/src/mnemonics/portuguese.h
+++ b/src/mnemonics/portuguese.h
@@ -26,6 +26,12 @@
 // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
 // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+/*!
+ * \file portuguese.h
+ * 
+ * \brief Portuguese word list and map.
+ */
+
 #ifndef PORTUGUESE_H
 #define PORTUGUESE_H
 
@@ -34,6 +40,10 @@
 #include "language_base.h"
 #include <string>
 
+/*!
+ * \namespace Language
+ * \brief Mnemonic language related namespace.
+ */
 namespace Language
 {
 	class Portuguese: public Base
diff --git a/src/mnemonics/singleton.h b/src/mnemonics/singleton.h
index 74cc290fc..5a86c2e7c 100644
--- a/src/mnemonics/singleton.h
+++ b/src/mnemonics/singleton.h
@@ -26,8 +26,26 @@
 // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
 // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+/*!
+ * \file singleton.h
+ * 
+ * \brief A singleton helper class based on template.
+ */
+
+/*!
+ * \namespace Language
+ * \brief Mnemonic language related namespace.
+ */
 namespace Language
 {
+	/*!
+	 * \class Singleton
+	 * 
+	 * \brief Single helper class.
+	 * 
+	 * Do Language::Singleton<YourClass>::instance() to create a singleton instance
+ 	 * of `YourClass`.
+	 */
 	template <class T>
 	class Singleton
 	{
diff --git a/src/mnemonics/spanish.h b/src/mnemonics/spanish.h
index c205adc95..efa71a202 100644
--- a/src/mnemonics/spanish.h
+++ b/src/mnemonics/spanish.h
@@ -27,6 +27,12 @@
 // STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
 // THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+/*!
+ * \file spanish.h
+ * 
+ * \brief Spanish word list and map.
+ */
+
 #ifndef SPANISH_H
 #define SPANISH_H
 
@@ -35,6 +41,10 @@
 #include "language_base.h"
 #include <string>
 
+/*!
+ * \namespace Language
+ * \brief Mnemonic language related namespace.
+ */
 namespace Language
 {
 	class Spanish: public Base