diff --git a/src/01-einfuehrung/hello-world/hello.ts b/src/01-einfuehrung/hello-world/hello.ts
index 28e5687..c6f2f54 100644
--- a/src/01-einfuehrung/hello-world/hello.ts
+++ b/src/01-einfuehrung/hello-world/hello.ts
@@ -1,2 +1,2 @@
-const message: string = 'Hello, World!';
-console.log(message);
+const helloworld: string = 'Hello, World!';
+console.log(helloworld);
diff --git a/src/02-syntax/tsconfig.json b/src/02-syntax/tsconfig.json
new file mode 100644
index 0000000..c222126
--- /dev/null
+++ b/src/02-syntax/tsconfig.json
@@ -0,0 +1,11 @@
+{
+  "compilerOptions": {
+    "target": "es2016",
+    "module": "commonjs",
+    "esModuleInterop": true,
+    "forceConsistentCasingInFileNames": true,
+    "strict": true,
+    "skipLibCheck": true,
+    "noImplicitAny": true
+  }
+}
diff --git a/src/02-syntax/typinferenz.ts b/src/02-syntax/typinferenz.ts
new file mode 100644
index 0000000..fc71dd9
--- /dev/null
+++ b/src/02-syntax/typinferenz.ts
@@ -0,0 +1,4 @@
+let inferredCount = 100;
+let inferredMessage = 'Automatic detection';
+
+// inferredMessage = 43;
diff --git a/src/02-syntax/typsystem.ts b/src/02-syntax/typsystem.ts
new file mode 100644
index 0000000..f45ca11
--- /dev/null
+++ b/src/02-syntax/typsystem.ts
@@ -0,0 +1,41 @@
+// const name: string = 'John';
+// const age: number = 30;
+// const isActive: boolean = true;
+const message = 'World';
+
+const total: number = 10 + 20;
+const greeting: string = `Hello, ${message}!`;
+const isActive: boolean = total > 20;
+
+let unknownValue: unknown = { message: 'Can be anything' };
+let anyValue: any = { count: '42' };
+
+let nullableValue: null = null;
+let undefinedValue: undefined = undefined;
+let mixedType: number | string = 'flexible type';
+mixedType = 100;
+// mixedType = true;
+
+// console.log(unknownValue)
+
+let valueAny: any;
+
+// value = 42;
+// value = true;
+// value = 'Hello';
+
+// let numberValue: number = value;
+// console.log(numberValue * 2);
+
+let value: unknown;
+
+value = true;
+value = 'Hello';
+value = 42;
+
+if (typeof value === 'number') {
+  let numberValue: number = value;
+  console.log(numberValue * 2);
+} else {
+  console.log('value ist keine number');
+}
diff --git a/src/02-syntax/variablen.ts b/src/02-syntax/variablen.ts
new file mode 100644
index 0000000..b0d56f6
--- /dev/null
+++ b/src/02-syntax/variablen.ts
@@ -0,0 +1,47 @@
+// const name: string = 'John';
+// const age: number = 30;
+// const isActive: boolean = true;
+
+const user = {
+  name: 'John',
+};
+
+console.log(age, isActive);
+
+// name = "Alex";
+let city = 'Berlin';
+city = 'Frankfurt';
+
+var address = {
+  city: 'Berlin',
+};
+
+function greet(name: string): string {
+  return `Hello, ${name}`; // "Hello " + name
+}
+
+console.log(greet('John'));
+
+const zahl: number = 10;
+
+if (zahl > 5) {
+  console.log('Zahl ist größer als 5');
+} else if (zahl === 6) {
+  console.log('Zahl ist 6');
+} else {
+  console.log('Zahl ist kleiner');
+}
+
+for (let i = 0; i < 3; i++) {
+  console.log(`Durchlauf: ${i}`);
+}
+
+function testVar() {
+  for (var i = 0; i < 3; i++) {
+    console.log(`i: ${i}`);
+  }
+
+  console.log(i);
+}
+
+console.log('test var: ', testVar());