pip3 is a Python package installer that can be used to install, upgrade, and uninstall Python packages. It’s named after “Pip Installs Packages”. pip3 specifically refers to the version of pip that is used for Python 3.

You can use pip3 from the command line as follows:

• Install a package: pip3 install <package_name>
• Upgrade a package: pip3 install --upgrade <package_name>
• Uninstall a package: pip3 uninstall <package_name>
• List installed packages: pip3 list
• Search for a package: pip3 search <package_name>

Remember to replace <package_name> with the actual name of the package you want to interact with.

Please note that as of Python 3.4, pip3 comes pre-installed with Python, so you do not need to install it separately. However, in some cases, you might need to upgrade pip3 itself using the following command: python3 -m pip install --upgrade pip

Remember that you may need appropriate permissions to install packages, so you might need to use sudo in Unix-based systems or run the command prompt as an administrator in Windows.