diff --git a/LanguageServer/src/main/java/org/nittalab/dtram/languageserver/model/Constants.java b/LanguageServer/src/main/java/org/nittalab/dtram/languageserver/model/Constants.java
new file mode 100644
index 0000000..9cbf274
--- /dev/null
+++ b/LanguageServer/src/main/java/org/nittalab/dtram/languageserver/model/Constants.java
@@ -0,0 +1,23 @@
+package org.nittalab.dtram.languageserver.model;
+
+/**
+ * {@link Constants} class holds all constants values used in DTRAM.
+ *
+ * @author Shohei Yamagiwa
+ * @since 0.1
+ */
+public class Constants {
+    /**
+     * Constants for language specific.
+     */
+    public static final String NIL = "nil";
+    public static final String NULL = "null";
+    public static final String TRUE = "true";
+    public static final String FALSE = "false";
+
+    /**
+     * Constants for Math
+     */
+    public static final String PI = "PI";
+    public static final String E = "E";
+}
diff --git a/LanguageServer/src/main/java/org/nittalab/dtram/languageserver/model/Functions.java b/LanguageServer/src/main/java/org/nittalab/dtram/languageserver/model/Functions.java
new file mode 100644
index 0000000..abcfa9c
--- /dev/null
+++ b/LanguageServer/src/main/java/org/nittalab/dtram/languageserver/model/Functions.java
@@ -0,0 +1,37 @@
+package org.nittalab.dtram.languageserver.model;
+
+/**
+ * {@link Functions} class holds all function names used in DTRAM.
+ *
+ * @author Shohei Yamagiwa
+ * @since 0.1
+ */
+public class Functions {
+    /**
+     * Functions for collection manipulation
+     */
+    public static final String APPEND = "append";
+    public static final String REMOVE = "remove";
+    public static final String INSERT = "insert";
+    public static final String DELETE = "delete";
+
+    /**
+     * Functions for conditional
+     */
+    public static final String IF = "if";
+
+    /**
+     * Functions for Math calculation
+     */
+    public static final String SQRT = "sqrt";
+    public static final String SIN = "sin";
+    public static final String COS = "cos";
+    public static final String TAN = "tan";
+    public static final String ASIN = "asin";
+    public static final String ACOS = "acos";
+    public static final String ATAN = "atan";
+    public static final String POW = "pow";
+    public static final String EXP = "exp";
+    public static final String LOG = "log";
+    public static final String ABS = "abs";
+}
diff --git a/LanguageServer/src/main/java/org/nittalab/dtram/languageserver/model/Types.java b/LanguageServer/src/main/java/org/nittalab/dtram/languageserver/model/Types.java
new file mode 100644
index 0000000..91bde38
--- /dev/null
+++ b/LanguageServer/src/main/java/org/nittalab/dtram/languageserver/model/Types.java
@@ -0,0 +1,21 @@
+package org.nittalab.dtram.languageserver.model;
+
+/**
+ * {@link Types} class holds all types used in DTRAM.
+ *
+ * @author Shohei Yamagiwa
+ * @since 0.1
+ */
+public class Types {
+    public static final String INTEGER = "Int";
+    public static final String LONG = "Long";
+    public static final String FLOAT = "Float";
+    public static final String DOUBLE = "Double";
+    public static final String BOOLEAN = "Bool";
+    public static final String STRING = "Str";
+    public static final String LIST = "List";
+    public static final String PAIR = "Pair";
+    public static final String TUPLE = "Tuple";
+    public static final String MAP = "Map";
+    public static final String JSON = "Json";
+}