JavaScript and why capital letters sometimes work and sometimes don't


In JavaScript, capitalization is important because JavaScript is a case-sensitive language. This means that JavaScript distinguishes between uppercase and lowercase letters and treats them as separate entities.

For example, if you define a variable with the name “myVariable”, you cannot access it using “MyVariable” or “myvariable”. JavaScript will treat these as different variables altogether.

However, there are some cases where capitalization may appear to work inconsistently. One common example is with built-in JavaScript functions and objects, where capitalization is often used to denote a constructor function.

For example, the Date object in JavaScript is a constructor function that can be used to create new Date objects. While the Date object is spelled with a capital “D”, it can also be accessed with a lowercase “d” in some cases. This is because JavaScript automatically converts the lowercase “d” to an uppercase “D” when it encounters it in certain contexts.

Here’s an example:

// Create a new Date object using the Date constructor function
const myDate = new Date();

// Access the Date object with a lowercase "d"
const myDate2 = new date(); // This will throw a "ReferenceError: date is not defined" error

In this example, new Date() will create a new Date object using the constructor function. However, new date() will throw a ReferenceError because date is not defined as a constructor function.

So while capitalization is important in JavaScript, there are some cases where JavaScript may interpret lowercase letters as uppercase in certain contexts. However, it is still important to use consistent capitalization in your code to avoid confusion and errors.