Basic Linux commands

What are the basic Linux commands to:

1.To view what's written in the file :

cat filename: This command is used to display all the contents in the particular file on the terminal.

2.To change the access permissions of the file:

chmod777 filename: This command is used to provide the permissions to the owner, group and others as a three-digit number.

Various digits and their permissions are listed below:

0: (000) No permission.
1: (001) Execute permission.
2: (010) Write permission.
3: (011) Write and execute permissions.
4: (100) Read permission.
5: (101) Read and execute permissions.
6: (110) Read and write permissions.
7: (111) Read, write and execute permissions.

3.To check the commands you have run till now.

history: This command is used to list all the commands we've used recently.

4.To remove a directory or a folder:

rmdir: Deleting an empty directory has the special command rmdir, which only removes an empty directory, protecting you from recursive mistakes.

5.To create a fruits.txt file and to view the content:

touch filename: This command is used to create a file.

cat filename: This command is used to display all the contents in the file.

Here we've created a file named fruits.txt and to access the contents from the file we've used the cat fruits.txt command

6.Add content in devops.txt (One in each line) - Apple, Mango, Banana, Cherry, Kiwi, Orange, Guava.

echo "contents" >> filename: We can use the echo command to add content to the file line by line.

7.To Show only the top three fruits from the file.

head -n: This command is used to display the top n contents in the file.

8.To Show only the bottom three fruits from the file.

tail -n: This command is used to display the bottom n contents in the file.

9.To create another file colors.txt and to view the content.