 So, we are looking at the complexities of creating and maintaining database website, database enabled website, okay. And even if it's not database enabled and it will become database enabled, you have to be very careful about the naming conventions. Why naming conventions are important here, number of reasons for it, okay. Say for because the thing is that you are developing your website not in real time online, okay. You are developing it on your in certain environment and then you upload them, right or not. And the thing is that even if you first for a certain kind of environment, you were not doing this, even if you are renaming your files, very soon you will lose track. You will have similar files with different names, okay, or different files with same name. It will be a disaster because there are not few files, there are quite a few number of files and the complexity grows. Then is the version control. So what is the module coverage? It is before you renaming the files, it should not be done. This is that 8.3, 8.3 kind of methodology of naming, which is very restrictive, okay. It's physical old days of DOS. I will talk about it. And being restrictive has its own advantages. Keeping track of the files, what were the names of the files, where they are placed and so on and establishing directories and folders to ensure you know where something is and of course to avoid renaming and changing and as the reasoning. So the details, never ever rename the files, never ever, okay. Moving the files to another directory, okay, with the same name. This is same as renaming the files because you know that, okay, this is the directory, this is directory A, this is directory B, say for example. And both directories have a file with the same name, okay, and you will say that using the path I can differentiate them, but at the end of the day, it is same as renaming the files. Don't do this. Now a web base, a web application, which is for the web is complex and it gets more complex when you have a database connected to it, okay. This is the point over here, database connected at the back end. It becomes more complex. Why? Because there is more diversity, there's more diversity and there's limited freedom on the web, on the website, because there is that directory in which you have this access and within that you are doing as per the permission as opposed to your own computer, as opposed to your own development environment, where you can do all sorts of things. You are the complete freedom. So you don't expect that kind of freedom will be available to you where you are hosting your application. It will not be there and varying naming and moving conventions like people have different likes and dislikes or personalities, the way in which they speak, the way in which they can maybe identify certain things to different computers and different operating systems. They have their own kind of unique environments, okay, and the naming conventions will vary. So you have to take into all of this into account, otherwise it's a chaos and very soon you will be kind of drowning in that chaos. 8.3 and capitalization. What is 8.3? Most restrictive program, for example, this example, one, two, three, four, five, six, okay, you can see over here, you have three over here and over here, three over here, so six and seven, so not more than eight. This is the dot. This is the dot. Okay. And this is the file extension three. This is the most restrictive naming convention. So it is available and it is going to be supported most likely on different environments. MacOS what it does, it does, it takes the suffix from the inside the file, from there it takes the suffix. Suffix is what is coming after the dot. And in UNIX, there are multiple suffix. 8.3 works for most platforms. Now UNIX is case sensitive, UNIX is case sensitive, okay, I don't know. So which you, I believe you understand, so in UNIX, for example, AS is not same as AS and is not same as you understand. Now remember that this is one thing. Don't expect all the operating systems to be case sensitive. If you have to use case, you are not using the case to differentiate between the names, but to make it more readable, okay, readability. Only then you are using the case. Keeping track of files, folders, folders may disappear on a website where it is loaded, where it is work. It has happened. It can happen to you also. So what you need to do is record what is placed where and you keep that record in a database at your end on your computer, okay, and critical for recovering from accidental housekeeping activities. So you keep that backup, what was placed where and if you, and of course you also keep what what actually was there, not only what was placed there, but you keep a backup listing also you, I believe you understand the difference between them. One is the structure you keep record and of course the backup which we have covered in the previous module. So why because it may so happen that you accidentally make deletion, you have to be careful about it. Exception directories and special purpose folder directory hierarchy to avoid renaming. The point over here is that for example, if you say there is a file name say orders and then you have a file name dot receipts, say for example, so and you make these file names like this, it is better that you have a directory and in that main directory you have a directory of corresponding to those file names and then you place the corresponding data or files under those sub directories. Then you know what you are looking for where is located, okay, and don't mix directories, don't mix directories web services, they can by default they have they are programmed and designed and developed to access data from a certain default file structure, and hierarchy of the directory structure also. Now if you mix the directories, it will confuse, it will make it difficult for the web server. Within each directory place the files default dot htm index dot htm home dot htm because then it prevents from displaying the contents, it will show the contents of these files. Use special folders for revisioning. Now remember one thing that something goes with which you would like to do professionally that you put the update date on the page that might go against you bad for in free because there are certain pages which don't change over a period of time that would give an impression to the visitor to a website that it is outdated, it is not outdated, that page does not change as frequently. So put that into a hidden field, put it into the header. So when you put it into the head, head tags, then it will not display to the visitor but you can check the head tag in the contents and know and of course database support versioning also you should know it, keep use of it, make use of it and that will help you manage your complex application, web-based database application. That is what I have the message for you in this module.