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JavaScript

Posted by Max van den Berge
Max van den Berge
6,506 Points

Uppercase and lowercase letter Function.

Hi all,

I have a question, i noticed that some build-in JS function start with an Uppercase letter and some with a lowercase letter.

for instance: alert(); or document.getElementById(id); start with a lowercase letter

and

Math.random (); starts with an Uppercase letter.

can someone help me to understaind when it starts with an Uppercase letter or with a lowercase letter, since JS is case sensitive ?

kind regard and many thanks!

gr. Max

2 Answers

babyoscar
babyoscar
12,930 Points

Usually, built-in JavaScript functions start with a lower case letter. The upper case part of Math.random() ("M" in "Math") is actually the first letter of the object that has the function as one of its properties, not the actual function ("random" is the function). Hope this helped!

Clayton Perszyk
MOD
Clayton Perszyk
Treehouse Moderator 48,850 Points
Clayton Perszyk
Clayton Perszyk
Treehouse Moderator 48,850 Points

In the case of Math.random(), the method is called directly on the object (ie a static method). Other methods are called on an instance of an object (ie calling new to invoke a constructor).

Max van den Berge
Max van den Berge
6,506 Points

thank you for sharing your knowledge, i now understand it better :)