Hey Friends Welcome back. Now in this part we are going to learn about Linux file system and about some commands. So let's start for executing a command does generals syntax of various shell commands on terminal begins with the command itself and the options and the arguments provided the options or arguments could be preceded by either a single character or multiple character. For example, ls l would be a command and there are options or could be minus a minus b minus C A B C or minus is placed before that character if it is a single letter argument, if we do have full word, option or argument, it is preceded by double dash or double minus symbol So there are two basic commands that only a few people use, date and calendar. Date command is used to check the current date and time which is being displayed on the screen.

And ca l or calendar displays you the calendar of the current month and year. But if you want to display a calendar for a certain month of a certain year, you don't need to swipe back to simply right for example, if my birth here is July 1995, and I just wanted to check when I was born, which day was there, I can check it by just writing ca L. His pace, month name month number. for July we have seven Cal seven is face 1995. It will display the month calendar of July 1995 similar Rarely you can do so, for any month of the year. There are ways kinds of health options when you get any trouble relative to any command or anything else on Linux environment. In redhead we can have help like what is for example, if you are confused with a command, what does this command do actually, the simply type what is without any space, then write a space and write a command for example, I have doubt related to date command.

So, I will write what is his paste date simply and press enter. It will tell you some detail about what does this command do some arguments and details related to that argument. Similarly, you can also type help command is pace, double dash symbol and have similarly you can A check manual and information by a man and info command. You can also go through the documentation, which is stored in user share and talk. You can navigate with arrows up and down page up and page down keys in the manual page. You can also search for text by just writing a slash text.

You can for example, if you have multiple matches on the screen, you can go to previous match your next match by just typing is small and n capital N respectively, is small n gives you muscle to the next match and capital and moves you to the previous match. The small q means quit when you want to terminate the execution of a certain Command just simply type a small q command a small q will terminate the execution of that command man minus k keyword list all matching pages and it uses what is database file system. Linux file system is far different from Windows or Mac. in Linux we have certain folders for example in Windows you might have seen drives like CD and everything is stored within these drives. See our C Drive is reserved for operating system files and other files system files and D and other partitions from word that you create is for you storage but in Linux there are various file systems where and file various directories or folders where everything is arranged.

You You have home directory which is the root directory for a user we will be learning it in the next slide. so files and directories are organized in a single routed inverted tree structure inverted v means a single folder on the top and rest other folders are derived from it. The single folder is called a slash or root directory that is forward slash and names of the file system are case sensitive. All of them in small parts are delimited by forward slash root. So, this is the Linux file system. Here root or forward slash is the parent of all the directories.

And whatever you see here, these directories or folders are derived from root and each directory is a diff has a defined objective. For example, beanie stores executables user executables boot a store server loading files. They are different thing Dev, dv, etc home which is a home directory for users. For eight has multiple user directories for user 123 and other so users library Li B, Mount amenti, Mt o PT option PLC process, root under folder has been temp user and where these are the directories and we will learning about these directories let so far the path for home directories could be a slash route. Everything begins with a slash forward slash that is a parent directory for everything. A slash route is the home directory for the route or a slash home and slash user name for other users.

For example for Andrew the home directory would be home use Andrew user executables are stored in been user bin, user slash local slash bin. different locations system executables executables are stored in s bin that is system executable when binary user slash system bin user slash local slash system when other mount points where you can mount exit external devices like CD pendrive and other drives can be mounted on media or amenti. Mount configuration files are stored in etc. temporary files or cache files are stored in temp kernels and bootloader files Restoring good Server Data is historian we are variable our server SRV system informations are stored in proc and says and shared libraries are stored in library user library, use a local memory. Remember this thing if you are preparing for red head examinations, that that is could be asked and it is very vital if you are not just simply preparing for the examinations, you must know where the executables or different files go.

So, if you are to administer your OS the file management have various commands to manage those files, create copy, delete, move, and various other things. Nautilus is a genome graphical file system browser which you can use To browse different files or folders on your screen on, next up, there is a very useful command that I personally like that is links Li nk s, it could be used as a command line web browser. alternative to anything. You can run command complete browser. On on your command line interface, it will not open up the images. That is a secured mode.

You can say images from a content virus and if you are in a low, slow connection internet connection. When you are interested in browsing any website, just simply write Li n Ks command links provide a space then type the complete URL of the website. For example, I want to open google.com so I will write triple w.google.com it will open the Google and language terminal There you can use your mouse or keyboard buttons to navigate through. The shells is stored in the home directory and which can be displayed by writing pwd command or display current directory or you can say print working directory, pwd command. Then you can use CD change directory. For a wide range of uses that we are going to learn next page.

Ls is used for list two directory content. If we want to see what files and folders are within a folder for example, suppose we have a folder called ABC. And we are interested in getting details about what what files and folders this folder ABC contains. We just simply need to write ls command and it will show you all The files and folders. Similar command is dir which is also available in Windows. dir command also runs on Linux.

Both functionality is the common functionality of both the commands is same to display files and folders. But there is a difference between LS and Dir. With dir you will see all the folders and file names in same color that is generally white. And with ls command. multiple files are based on different format for example, a text files are displayed with yellow color. C files are displayed in pink color or folders names are displayed with white color and so on.

He will get through easily It is helpful in navigation. You can manage files, copy CP, move MV, and RM remove Similarly we can do so called directories or files. Let's understand about these two commands LS and CD in detail. If you want to browse through a certain folder certain directory, just navigate right CD and write the exact path of the dat file or folder. Similar suppose I want to navigate to the music folder placed in Simon which is placed in home directory. So we have to write CD slash home slash Simon's is slash music.

If you want to play any music, just provide the name of the music with extension and press the Enter button. CD actually navigates you to the folder. It is not used to run the file. It needs permissions you can go to our directory one level of suppose we are here in the music and we want to go to Sam's folder or directory. What we have to do we have to write cd space double.it will move one folder up. If you are ready, you are inside folder inside folder inside folder and we just wanted to move to the home directory without typing again and again CD dot dot, just simply write CD, it will lead to the home directory.

Similarly, if you want to go to the previous working directory, you can go with a CD minus four ls command we have different options. ls minus A will show files with hidden files included. hidden files is also displayed when you write minus A option. minus l will show you extra information about files minus r we recurse through directories and minus LD will show you directory and symlink information. We can do copy and move operations. By with CP and MV command.

MV move means simply cut and paste shortened for move, if you just simply do copy, the original file is a key in tech and a new copy of that file is made in another location. But you move that file, the original location does not contains a file anymore. It is placed in a new location. For moving of file just write CP If we want to write any option, just provide the option. Otherwise keep it blank. Write the name of the file, which you want to copy the full path of the file.

For example, I want to copy a file called a dot txt kept him etc. So I will write a slash etc slash a dot txt after writing CP, then I will write the destination where I want to paste that file. It will be copied. Similarly for move, I can do something. If I want to copy or move multiple files at the same time, just simply write the path for the multiple files that we'll be using. You can create and delete files.

You can create file with our touch, command and delete with delete With remove RM, touch will create a file. For example, if you want to create a file called ABC dot java, so just simply write command touch space, ABC dot java, we'll be doing practical. So don't worry, just try to learn these things. And if you does not do not type the complete format for a file, it will simply create a binary file. For example, if you agree, right girge is paced say assignments. It will create a file called name assignment without any extension, or which is a binary file.

So don't do that thing always provide you a file format. Similarly, you can remove files with RM RM write RM displays to file them the complete path it will be to move. You could also provide a directory when you want a recursive operation or minus F for force, and I for interactive options. mk dir command is used to create directories or folders rmdir is used to remove a directory MD. Sorry, RM was used to delete files, but RM dir is used to delete folder. That's the difference within these commands.

So we have learned about fundamentals of file system and certain simple commands with arguments Give it a try and try to make your own files, move them from one folder to other, remove them, copy them, move them and test these commands. Create your file and edit your file. So keep learning keep moving ahead. We will be learning more commands and other details on arch here in the coming videos