diff --git a/gcc/elna-generic.cc b/gcc/elna-generic.cc
index 60cdc87..b0cfa13 100644
--- a/gcc/elna-generic.cc
+++ b/gcc/elna-generic.cc
@@ -250,7 +250,12 @@ namespace gcc
 
     void generic_visitor::visit(source::number_literal<std::int32_t> *literal)
     {
-        this->current_expression = build_int_cst_type(integer_type_node, literal->number());
+        this->current_expression = build_int_cst(integer_type_node, literal->number());
+    }
+
+    void generic_visitor::visit(source::number_literal<std::uint32_t> *literal)
+    {
+        this->current_expression = build_int_cstu(unsigned_type_node, literal->number());
     }
 
     void generic_visitor::visit(source::number_literal<double> *literal)
diff --git a/include/elna/gcc/elna-generic.h b/include/elna/gcc/elna-generic.h
index ea280dd..8169126 100644
--- a/include/elna/gcc/elna-generic.h
+++ b/include/elna/gcc/elna-generic.h
@@ -41,6 +41,7 @@ namespace gcc
         void visit(source::procedure_definition *definition) override;
         void visit(source::call_expression *statement) override;
         void visit(source::number_literal<std::int32_t> *literal) override;
+        void visit(source::number_literal<std::uint32_t> *literal) override;
         void visit(source::number_literal<double> *literal) override;
         void visit(source::number_literal<bool> *boolean) override;
         void visit(source::number_literal<unsigned char> *character) override;
diff --git a/include/elna/source/ast.h b/include/elna/source/ast.h
index fa61997..c3cae7b 100644
--- a/include/elna/source/ast.h
+++ b/include/elna/source/ast.h
@@ -94,6 +94,7 @@ namespace source
         virtual void visit(field_access_expression *is_field_access) = 0;
         virtual void visit(dereference_expression *is_dereference) = 0;
         virtual void visit(number_literal<std::int32_t> *) = 0;
+        virtual void visit(number_literal<std::uint32_t> *) = 0;
         virtual void visit(number_literal<double> *) = 0;
         virtual void visit(number_literal<bool> *) = 0;
         virtual void visit(number_literal<unsigned char> *) = 0;
@@ -130,6 +131,7 @@ namespace source
         virtual void visit(field_access_expression *expression) override;
         virtual void visit(dereference_expression *expression) override;
         virtual void visit(number_literal<std::int32_t> *) override;
+        virtual void visit(number_literal<std::uint32_t> *) override;
         virtual void visit(number_literal<double> *) override;
         virtual void visit(number_literal<bool> *) override;
         virtual void visit(number_literal<unsigned char> *) override;
diff --git a/include/elna/source/driver.h b/include/elna/source/driver.h
index 36ba93a..de4dead 100644
--- a/include/elna/source/driver.h
+++ b/include/elna/source/driver.h
@@ -4,6 +4,7 @@
 #pragma once
 
 #include <list>
+#include <optional>
 #include "elna/source/ast.h"
 #include "location.hh"
 
@@ -37,5 +38,7 @@ namespace source
         void error(const yy::location& loc, const std::string& message);
         const std::list<std::unique_ptr<struct error>>& errors() const noexcept;
     };
+
+    std::optional<char> escape_char(char escape);
 }
 }
diff --git a/source/ast.cc b/source/ast.cc
index b082640..13388ee 100644
--- a/source/ast.cc
+++ b/source/ast.cc
@@ -167,6 +167,10 @@ namespace source
     {
     }
 
+    void empty_visitor::visit(number_literal<std::uint32_t> *)
+    {
+    }
+
     void empty_visitor::visit(number_literal<double> *)
     {
     }
diff --git a/source/driver.cc b/source/driver.cc
index 4b35d27..c58324f 100644
--- a/source/driver.cc
+++ b/source/driver.cc
@@ -40,5 +40,38 @@ namespace source
     {
         return m_errors;
     }
+
+    std::optional<char> escape_char(char escape)
+    {
+        switch (escape)
+        {
+        case 'n':
+            return std::make_optional<char>('\n');
+        case 'a':
+            return std::make_optional<char>('\a');
+        case 'b':
+            return std::make_optional<char>('\b');
+        case 't':
+            return std::make_optional<char>('\t');
+        case 'f':
+            return std::make_optional<char>('\f');
+        case 'r':
+            return std::make_optional<char>('\r');
+        case 'v':
+            return std::make_optional<char>('\v');
+        case '\\':
+            return std::make_optional<char>('\\');
+        case '\'':
+            return std::make_optional<char>('\'');
+        case '"':
+            return std::make_optional<char>('"');
+        case '?':
+            return std::make_optional<char>('\?');
+        case '0':
+            return std::make_optional<char>('\0');
+        default:
+            return std::nullopt;
+        }
+    }
 }
 }
diff --git a/source/lexer.ll b/source/lexer.ll
index 2711b39..c056d94 100644
--- a/source/lexer.ll
+++ b/source/lexer.ll
@@ -106,6 +106,9 @@ return                  {
 [A-Za-z_][A-Za-z0-9_]*  {
                             return yy::parser::make_IDENTIFIER(yytext, this->location);
                         }
+[0-9]+u                 {
+                            return yy::parser::make_WORD(strtoul(yytext, NULL, 10), this->location);
+                        }
 [0-9]+                  {
                             return yy::parser::make_INTEGER(strtol(yytext, NULL, 10), this->location);
                         }
@@ -113,7 +116,7 @@ return                  {
                             return yy::parser::make_FLOAT(strtof(yytext, NULL), this->location);
                         }
 '[[:print:]]'           {
-                            if (yytext[1] == '\\')
+                            if (yytext[1] == '\\' || yytext[1] == '\'')
                             {
                                 REJECT;
                             }
@@ -122,45 +125,66 @@ return                  {
                                 return yy::parser::make_CHARACTER(std::string(yytext, 1, 1), this->location);
                             }
                         }
-'\\x[0-9a-fA-F]{2}'     {
+'\\x[0-9a-fA-F]{1,2}'     {
                             char character = static_cast<char>(std::stoi(yytext + 3, nullptr, 16));
 
                             return yy::parser::make_CHARACTER(std::string(&character, 1), this->location);
                         }
 '\\[0nabtfrv\\'"?]'     {
-                            switch (yytext[2])
+                            std::optional<char> escape = source::escape_char(yytext[2]);
+                            if (escape.has_value())
+                            {
+                                return yy::parser::make_CHARACTER(std::string(&escape.value(), 1), this->location);
+                            }
+                            else
                             {
-                                case 'n':
-                                    return yy::parser::make_CHARACTER(std::string("\n"), this->location);
-                                case 'a':
-                                    return yy::parser::make_CHARACTER(std::string("\a"), this->location);
-                                case 'b':
-                                    return yy::parser::make_CHARACTER(std::string("\b"), this->location);
-                                case 't':
-                                    return yy::parser::make_CHARACTER(std::string("\t"), this->location);
-                                case 'f':
-                                    return yy::parser::make_CHARACTER(std::string("\f"), this->location);
-                                case 'r':
-                                    return yy::parser::make_CHARACTER(std::string("\r"), this->location);
-                                case 'v':
-                                    return yy::parser::make_CHARACTER(std::string("\v"), this->location);
-                                case '\\':
-                                    return yy::parser::make_CHARACTER(std::string("\\"), this->location);
-                                case '\'':
-                                    return yy::parser::make_CHARACTER(std::string("'"), this->location);
-                                case '"':
-                                    return yy::parser::make_CHARACTER(std::string("\""), this->location);
-                                case '?':
-                                    return yy::parser::make_CHARACTER(std::string("\?"), this->location);
-                                case '0':
-                                    return yy::parser::make_CHARACTER(std::string("\0", 1), this->location);
-                            default:
                                 REJECT;
                             }
                         }
-\"[^\"]*\"              {
-                            return yy::parser::make_STRING(
-                                    std::string(yytext, 1, strlen(yytext) - 2), this->location);
+\"[[:print:]]*\"        {
+                            std::string result;
+                            const char *current_position = yytext + 1;
+
+                            while (*current_position != '\0')
+                            {
+                                if (*current_position == '\\' && *(current_position + 1) == 'x')
+                                {
+                                    current_position += 2;
+
+                                    std::size_t processed;
+                                    char character = static_cast<char>(std::stoi(current_position, &processed, 16));
+                                    if (processed == 0)
+									{
+									    REJECT;
+									}
+									else
+									{
+                                        current_position += processed - 1;
+                                        result.push_back(character);
+									}
+                                }
+                                else if (*current_position == '\\')
+                                {
+                                    ++current_position;
+
+                                    std::optional<char> escape = source::escape_char(*current_position);
+                                    if (escape.has_value())
+									{
+                                        result.push_back(escape.value());
+									}
+									else
+									{
+									    REJECT;
+									}
+                                }
+                                else
+                                {
+                                    result.push_back(*current_position);
+                                }
+                                ++current_position;
+                            }
+                            result.pop_back();
+                            return yy::parser::make_STRING(result, this->location);
                         }
 \(                      {
                             return yy::parser::make_LEFT_PAREN(this->location);
diff --git a/source/parser.yy b/source/parser.yy
index 8393b31..e7aa924 100644
--- a/source/parser.yy
+++ b/source/parser.yy
@@ -58,6 +58,7 @@
 
 %token <std::string> IDENTIFIER "identifier"
 %token <std::int32_t> INTEGER "integer"
+%token <std::uint32_t> WORD "word"
 %token <float> FLOAT "float"
 %token <std::string> CHARACTER "character"
 %token <std::string> STRING "string"
@@ -208,6 +209,10 @@ literal:
         {
             $$ = new elna::source::number_literal<std::int32_t>(elna::source::make_position(@1), $1);
         }
+    | WORD
+        {
+            $$ = new elna::source::number_literal<std::uint32_t>(elna::source::make_position(@1), $1);
+        }
     | FLOAT
         {
             $$ = new elna::source::number_literal<double>(elna::source::make_position(@1), $1);