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## Linux Paths
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.       # => the current working directory
..      # => the parent directory
~       # => the user's home directory

cd      # => changing the current directory to user's home directory
cd ~    # => changing the current directory to user's home directory
cd -    # => changing the current directory to the last directory
cd /path_to_dir    # => changing the current directory to path_to_dir 
pwd     # => printing the current working directory

# installing tree
sudo apt install tree

tree directory/     # => Ex: tree .
tree -d .           # => prints only directories
tree -f .           # => prints absolute paths