It is recommended to regularly update your Raspbian operating system. This can be done with these two apt-get commands:
sudo apt-get update – this command will update your system’s package list:
sudo apt-get upgrade – this command will upgrade all installed packages to the newest version. Before running this command, make sure that you have enough disk space (you can check the available disk space with the df -h command). The sudo apt-get upgrade command will display how much space is needed to perform the upgrade.