INTRODUCTION TO UNIX

kernel is the core of the operating system that controls all the tasks of the system while the shell is the interface that allows the users to communicate with the kernel. shell accepts and interprets commands through a CLI(terminal)

Linux Commands we use extensively :

pwd : Which shows the path of the current working directory

ls: Lists the files and folders in the directory

cd: Move us from one directory to other

cd ..: It takes us one step back in the directories path

ls -l: Lists the long-format files and directories

clear : Which clears the screen

Manipulating the files:

touch file.txt: which creates file name called file.txt

echo “text you want to input to file ” > file.txt: you can input the text directly into file.txt through this command

head file.txt: which shows the first 10 lines of the file

tail file.txt: which shows last10 lines of the file

cat file.txt: shows the text inside the file

nano file.txt: nano editor opens the file.txt

grep search word <targetfile>: used to search for a string in a file.

mv file.txt file2.txt: it is more of like cut and paste of a file, file.txt will be renamed to file2.txt

cp <source path of file> <target path> : we can copy the files

we can make these commands powerful by options for example

ls -la: which shows all the hidden files and all files in long format

ls -S: which will display files in decrement manner of size

we can write our command in this way “ls -laS” also

cat file.txt | grep “search for the word”: which shows the lines consists of the search word.