update ubuntu in terminal

C
#gets package(s) update definitions
sudo apt update
#upgrades the package(s) for which update definitions are received
sudo apt upgrade
# "To update Linux type:"
sudo apt-get update
# Enter your user's password.sudo apt update && sudo apt upgrade -y
#or use it seperately
sudo apt update
sudo apt upgrade
#you make wanna run below command to remove unwanted
#and free up some space
sudo apt autoremovesudo do-release-upgrade
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