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Now that we learned a lot about numbers and big 

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integer,

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before we move on to strings, let's have a look at the number and the math global object.

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We used some of the features of these objects already and now I just want to have a second look and

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walk you through the important ones,

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let's start with number.

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There we saw MAX_SAFE_INTEGER, MAX_VALUE, MIN_SAFE_INTEGER and MIN_VALUE,

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you also have negative and positive infinity.

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These are special values in Javascript which you also can just type like this

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by the way, infinity and -infinity

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and this is the value you for example get if you divide by zero, you'll not get an error which you might

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expect,

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instead you get infinity because it basically approximates the result you could say.

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So infinity is a special value you can get and you can also check for infinity in places where you need

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true or false,

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for that you've got the isFinite method,

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also on the number object but also available just on a global object to which you can pass a number

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to find out if this is finite,

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like an example of 10 is true or if it's infinite

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as an example of infinity because that is not finite and therefore, this returns false.

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So number isFinite can be useful,

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we also have isNaN there,

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we saw that earlier already, also exists as a global method.

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We got parseFloat and parseInt here which also exists globally though and therefore we don't really need

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that here

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and that's therefore basically it for the number object.

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More interesting than that is the math object,

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there you get various methods and constants or properties that help you with mathematical operations.

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You've got the value for the E number, for Pi if you need that in calculations, methods for calculating

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the square root, for working with the sin for example,

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also the power of method

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we saw a second ago in this module already, the abs method to give you an absolute number based on some

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number you pass in as an input and many more methods, like for example also the random method you

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already learned about which also can often be very convenient.

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I can only recommend that you scroll through the various methods you've got there, as you can see, there are

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a lot, of course the MDN docs are also a great place to learn all about them and whenever you have

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a mathematical operation you need to perform in your code,

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chances are that you don't need to reinvent the wheel and you don't need to write your own logic but

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that the math object has got you covered and provides the operation you want to perform.