 So students, we are continuing with the housekeeping, good housekeeping in the code which we started in the last module. And in this module, we'll talk about the line breaks. And we will also talk about something very useful, which is the reserved words. Reserve words are the words which you cannot use in your code, because that are used by the JavaScript interpreter itself. So let's look at the outline. So this is the module outline line breaks, placing JavaScript correctly, JavaScript statements and the reserved words. And mind you that there are certain reserved words which are currently used, which I'll share with you and the reserved words, which are going to be available for the interpreter in the future. So avoid using them. So let's go into more details. So what are line breaks line breaks are called as carriage returns. And as per the European Computer Manufacturers Association, they are called as terminators also. Now, if you recall that the improper use of the semicolon created errors, so the improper use of the line breaks, similarly can create errors with reference to the return keyword. So what is the common application? The common application of this line break is the readability. The readability of long lines of code, the readability of single lines of code. And of course, this extra line break over here, that can create unwanted effects, extra line breaks. A similar example we had with reference to the return semicolon, the last module. Let's go into more details. So now that we know what was the issue with the line breaks, now where do we place the JavaScript? So we can place the JavaScript in the head section over here, or we can place it within the body tags over here also. Now, the placing of the script stands up within the body section is becoming more common. This is becoming more common. Why? Because sure to declare what type of script you are using, although other script types can be used, because this module is about JavaScript, we declare the following within the opening script, we declare it over here that we are using JavaScript. One important issue not okay noted, when you use JavaScript release, the pages declared as extensible hypertext markup language. Therefore, JavaScript used within strict x HTML should be declared as follows, like this. Okay, older browsers might not parse the C data section correctly, this section by the older browsers. Okay. So what to do? This problem can be worked around by placing the C data opening and closing lines within JavaScript comments like this. So use this approach, working around the old browsers. I believe you understand. Where do you place the JavaScript? Now, what you can also do is you can place the code in an external file also. Instead of the page itself, instead of the page, instead of the page itself, you can place it in external file. When you place the actual JavaScript code in a separate file, you don't need to use this ugly C data section at all in the previous module. You will probably discover that for anything but the smaller script defining your JavaScript in a separate files, usually with the file extension.js. Okay. Dot just over here. And then linking to those scripts within the page is desirable. Here's a reminder of how you link to a file using the source attribute of the script tag. This is how you place in an external file. Okay. Placing JavaScript in an external file has several advantages also, including the following. These are some of the advantages. For example, keeping the JavaScript code in a separate file makes maintaining the HTML easier, and it preserves the structure of the HTML without you having to use the C data section for XTML. So over here, you don't need the C data. Using JavaScript in a separate file, you can make changes to the JavaScript code in that separate file without touching the HTML. Okay. No, no touch. No touch HTML. All right. Using a separate file for JavaScript enables web browsers to cache the file, thus speeding up the web page load for the users. This cashing, feed up. Okay. Feed up. So JavaScript statements, what is the statement like programs written in other languages, JavaScript programs consist of statements put together that cause the JavaScript interpreter to perform one or more actions. And like statements in other languages, JavaScript statements can be simple or compound. Okay. This module briefly examines JavaScript statements. Right. So what's in a statement JavaScript is more than you might think a JavaScript statement or expression is a collection of tokens of various categories, including keywords. Okay. You have keywords. You have literals. Okay. And you have tokens. There are many things over here. A statement usually ends with a semicolon, except in special cases, the loop constructors such as if while and here are some examples of basic JavaScript statements over here, basic JavaScript statements. The two types of JavaScript statements, the JavaScript statement came in two basic forms, simple and compound will not spend a lot of time on it. All right. However, you should know the difference between simple and compound statements. A simple statement is just what you would expect. It's very simple. This is a simple statement. This is a compound statement. Okay. A compound statement combines multiple levels of logic. And if then else conditional, such as the one given here provides good example of this compound statement, simple statement. Okay. And we have these two types of statements. I think this should be clear now. So what are the reserved words? Certain words in JavaScript are reserved, which means you can't use them as variable identifiers or constant names within your program. Because doing so will cause the code to have unexpected results, such as errors. For example, you've already seen the reserved word var in previous examples. In previous example, you've already seen var. Okay. And using the word var to do anything but declare a variable can cause errors or other unexpected behavior depending on the browser. So over here, don't do this. Don't do this. Alright, so we have this currently set of reserved words, several other words shown in the following table are reserved for future use, and therefore, shouldn't be used in your programs. So these are the future ones. So I believe it should be clear to you, you have to be careful with using the reserved words. That's all for this module.