diff --git a/src/core/enums/errno.enum.ts b/src/core/enums/errno.enum.ts
index a7f6365..328e0b8 100644
--- a/src/core/enums/errno.enum.ts
+++ b/src/core/enums/errno.enum.ts
@@ -6,6 +6,8 @@ export enum Errno {
   InvalidFileError,
   UnknownFileError,
   MissingColonError,
+  InvalidArrayError,
+  InvalidStringError,
   MissingEqualsError,
   ExpectedCommaError,
   UnclosedStringError,
diff --git a/src/core/errors/index.ts b/src/core/errors/index.ts
index ab9e417..8ba91e4 100644
--- a/src/core/errors/index.ts
+++ b/src/core/errors/index.ts
@@ -4,7 +4,9 @@ export * from './missing-dot.error';
 export * from './unknown-file.error';
 export * from './expected-key.error';
 export * from './invalid-file.error';
+export * from './invalid-array.error';
 export * from './missing-colon.error';
+export * from './invalid-string.error';
 export * from './expected-comma.error';
 export * from './missing-equals.error';
 export * from './unclosed-string.error';
diff --git a/src/core/errors/invalid-array.error.ts b/src/core/errors/invalid-array.error.ts
new file mode 100644
index 0000000..b9e5241
--- /dev/null
+++ b/src/core/errors/invalid-array.error.ts
@@ -0,0 +1,13 @@
+import { Errno } from '../enums/errno.enum';
+import { LangKamaError } from './langkama.error';
+
+
+
+export class InvalidArrayError extends LangKamaError {
+  constructor() {
+    super('identifier is not a valid array');
+
+    this.name = 'InvalidArrayError';
+    this.errno = Errno.InvalidArrayError;
+  }
+}
\ No newline at end of file
diff --git a/src/core/errors/invalid-string.error.ts b/src/core/errors/invalid-string.error.ts
new file mode 100644
index 0000000..2231df6
--- /dev/null
+++ b/src/core/errors/invalid-string.error.ts
@@ -0,0 +1,13 @@
+import { Errno } from '../enums/errno.enum';
+import { LangKamaError } from './langkama.error';
+
+
+
+export class InvalidStringError extends LangKamaError {
+  constructor() {
+    super('name is not a string');
+
+    this.name = 'InvalidStringError';
+    this.errno = Errno.InvalidStringError;
+  }
+}
\ No newline at end of file
diff --git a/src/runtime/environment.ts b/src/runtime/environment.ts
index d9aeee2..cf4ea50 100644
--- a/src/runtime/environment.ts
+++ b/src/runtime/environment.ts
@@ -1,4 +1,4 @@
-import { ConstantReassignmentError, TOnStdOutCallbackFn, Type, VariableDefinedError, VariableNotDefinedError } from '..';
+import { ConstantReassignmentError, InvalidArrayError, InvalidStringError, TOnStdOutCallbackFn, Type, VariableDefinedError, VariableNotDefinedError } from '..';
 
 import { ErrorManager } from '../core/managers/error.manager';
 import { RuntimeHelper } from '../core/helpers/runtime.helper';
@@ -74,7 +74,7 @@ export class Environment {
       const [arr] = args;
 
       if (arr.type !== Type.Array) {
-        throw 'needs to be an array';
+        this.errorManager?.raise(new InvalidArrayError());
       }
 
       return RuntimeHelper.createNumber((arr as IArrayVal).value.length);
@@ -84,13 +84,13 @@ export class Environment {
       const [arrName, value] = args;
 
       if (arrName.type !== Type.String) {
-        throw 'needs to ne a string';
+        this.errorManager?.raise(new InvalidStringError());
       }
 
       const arrayVal = this.getValue((arrName as IStringVal).value).value as IArrayVal;
 
       if (arrayVal.type !== Type.Array) {
-        throw 'needs to be an array';
+        this.errorManager?.raise(new InvalidArrayError());
       }
 
       const newArray = [...arrayVal.value];
@@ -104,13 +104,13 @@ export class Environment {
       const [arrName] = args;
 
       if (arrName.type !== Type.String) {
-        throw 'needs to ne a string';
+        this.errorManager?.raise(new InvalidStringError());
       }
 
       const arrayVal = this.getValue((arrName as IStringVal).value).value as IArrayVal;
 
       if (arrayVal.type !== Type.Array) {
-        throw 'needs to be an array';
+        this.errorManager?.raise(new InvalidArrayError());
       }
 
       const newArray = [...arrayVal.value];
diff --git a/src/runtime/interpreter.ts b/src/runtime/interpreter.ts
index eb06926..b20c262 100644
--- a/src/runtime/interpreter.ts
+++ b/src/runtime/interpreter.ts
@@ -288,8 +288,9 @@ export class Evaluator {
     const index = this.evaluate(array.index, env) as INumberVal;
     const identifier = this.evaluate(array.identifier, env) as IArrayVal;
     const arr = (identifier as IArrayVal).value;
+    const value = arr[index.value];
 
-    return RuntimeHelper.createValue(arr[index.value]);
+    return value ? RuntimeHelper.createValue(value) : RuntimeHelper.createNull();
   }
 
   /**
diff --git a/test/arrays.test.js b/test/arrays.test.js
new file mode 100644
index 0000000..27eafe4
--- /dev/null
+++ b/test/arrays.test.js
@@ -0,0 +1,225 @@
+const Errno = require('../dist/@nakamaorg/langkama.umd.cjs').Errno;
+const LangKama = require('../dist/@nakamaorg/langkama.umd.cjs').LangKama;
+const LangKamaEvent = require('../dist/@nakamaorg/langkama.umd.cjs').LangKamaEvent;
+
+
+
+describe('Arrays', () => {
+  let compiler;
+
+  beforeEach(() => {
+    compiler = new LangKama();
+  });
+
+  test('Array declaration with value 1', done => {
+    const code = `
+      a sa7 hear me out arr[] is [];
+      reda arr;
+    `;
+
+    compiler
+      .on(LangKamaEvent.Success, result => {
+        expect(result.value).toEqual([]);
+        done();
+      })
+      .interpret(code);
+  });
+
+  test('Array declaration with value 2', done => {
+    const code = `
+      a sa7 hear me out arr[] is [1, 2, 3];
+      reda arr;
+    `;
+
+    compiler
+      .on(LangKamaEvent.Success, result => {
+        expect(result.value).toEqual([1, 2, 3]);
+        done();
+      })
+      .interpret(code);
+  });
+
+  test('Array declaration without value', done => {
+    const code = `
+      hear me out arr[];
+      reda arr;
+    `;
+
+    compiler
+      .on(LangKamaEvent.Success, result => {
+        expect(result.value).toEqual([]);
+        done();
+      })
+      .interpret(code);
+  });
+
+  test('Array indexing inbound', done => {
+    const code = `
+      a sa7 hear me out arr[] is [1, 2, 3];
+      reda arr[1];
+    `;
+
+    compiler
+      .on(LangKamaEvent.Success, result => {
+        expect(result.value).toBe(2);
+        done();
+      })
+      .interpret(code);
+  });
+
+  test('Array indexing out of bound', done => {
+    const code = `
+      a sa7 hear me out arr[] is [1, 2, 3];
+      reda arr[3];
+    `;
+
+    compiler
+      .on(LangKamaEvent.Success, result => {
+        expect(result.value).toBe(null);
+        done();
+      })
+      .interpret(code);
+  });
+
+  test('Array index assignment', done => {
+    const code = `
+      hear me out arr[] is [1, 2, 3];
+      arr[0] is 100;
+
+      reda arr;
+    `;
+
+    compiler
+      .on(LangKamaEvent.Success, result => {
+        expect(result.value).toEqual([100, 2, 3]);
+        done();
+      })
+      .interpret(code);
+  });
+
+  test('Array length', done => {
+    const code = `
+      hear me out arr[] is [1, 2, 3];
+      reda length(arr);
+    `;
+
+    compiler
+      .on(LangKamaEvent.Success, result => {
+        expect(result.value).toBe(3);
+        done();
+      })
+      .interpret(code);
+  });
+
+  test('Array push 1', done => {
+    const code = `
+      hear me out arr[];
+
+      push("arr", 0);
+      push("arr", 1);
+      push("arr", 2);
+
+      reda arr;
+    `;
+
+    compiler
+      .on(LangKamaEvent.Success, result => {
+        expect(result.value).toEqual([0, 1, 2]);
+        done();
+      })
+      .interpret(code);
+  });
+
+  test('Array push 2', done => {
+    const code = `
+      hear me out arr[];
+      hear me out i is 0;
+
+      cook until (i = 100) {
+        big if true ((i % 2) = 0) {
+          push("arr", i);
+        }
+
+        i is i + 1;
+      }
+
+      reda push("arr", 100);
+    `;
+
+    compiler
+      .on(LangKamaEvent.Success, result => {
+        expect(result.value).toBe(51);
+        done();
+      })
+      .interpret(code);
+  });
+
+  test('Array pop 1', done => {
+    const code = `
+      hear me out arr[] is [1, 2, 3];
+
+      pop("arr");
+      pop("arr");
+
+      reda arr;
+    `;
+
+    compiler
+      .on(LangKamaEvent.Success, result => {
+        expect(result.value).toEqual([1]);
+        done();
+      })
+      .interpret(code);
+  });
+
+  test('Array pop 2', done => {
+    const code = `
+      hear me out arr[];
+      hear me out i is 0;
+
+      cook until (i = 100) {
+        push("arr", i);
+        i is i + 1;
+      }
+      
+      i is 0;
+      cook until (i = 100) {
+        big if true ((i % 2) = 0) {
+          pop("arr");
+        }
+
+        i is i + 1;
+      }
+
+      reda pop("arr");
+    `;
+
+    compiler
+      .on(LangKamaEvent.Success, result => {
+        expect(result.value).toBe(49);
+        done();
+      })
+      .interpret(code);
+  });
+});
+
+describe('Arrays errors', () => {
+  let compiler;
+
+  beforeEach(() => {
+    compiler = new LangKama();
+  });
+
+  test('Missing close bracket', done => {
+    const code = `
+      hear me out arr[ is [];
+    `;
+
+    compiler
+      .on(LangKamaEvent.Error, result => {
+        expect(result.errno).toBe(Errno.ExpectedCloseBrackError);
+        done();
+      })
+      .interpret(code);
+  });
+});
\ No newline at end of file