 Hi, let's talk about functions in TypeScript and let's make a simple function. Functions in TypeScript are very familiar with functions in JavaScript and if you know JavaScript, you will find that it's very easy to create functions in TypeScript. For example, in JavaScript, we will make function something like this. Let's say function, for example, absolute value and let's put inside parentheses a variable. That variable will be a number which we want to provide to our function and finally at some point our function will return some value. If we want to define function in TypeScript, we need to provide more information about our function. We need to provide information about our arguments. We need to add type annotation to the parameter list. For example, here we have variable X and we need to say that our variable X has number type so it can be any float point number and then also in TypeScript, we need to provide additional information about our returning value. The type of our returning value will be also a number. It's very similar to define a function in TypeScript if you know JavaScript but you need to keep on mind that you need to provide additional information for your parameters and for your returning values. You need to provide their types. Okay, let's write absolute value function. For example, how absolute value works if we want to provide, for example, negative number minus 5, absolute value of minus 5 is 5 and if we want to provide number 5, the absolute value of number 5 is number 5. So if our provided number X is greater than zero, then we're going to return that exact same number and else if our variable X is less than zero or we could also say it's equal to zero, we will return minus X because here the absolute value of minus 5 is 5. That's because we're having minus of our minus 5 and minus and minus will give to us plus sign. So we're going to return minus X here and that's our function in TypeScript and it's very similar in JavaScript. They are almost the same but you need to provide types for your parameters and for your returning value. That's all in this lesson. Thanks for watching.