A clone is a copy of a virtual machine. A template is a master copy of a virtual machine that can be used to create many clones.
When you clone a virtual machine, you create a copy of the entire virtual machine, including its settings, any configured virtual devices, installed software, and other contents of the virtual machine's disks. You also have the option to use guest operating system customization to change some of the properties of the clone, such as the computer name and networking settings.
Cloning a virtual machine can save time if you are deploying many similar virtual machines. You can create, configure, and install software on a single virtual machine, and then clone it multiple times, rather than creating and configuring each virtual machine individually.
If you create a virtual machine that you want to clone frequently, make that virtual machine a template. A template is a master copy of a virtual machine that can be used to create and provision virtual machines. Templates cannot be powered on or edited, and are more difficult to alter than ordinary virtual machine. A template offers a more secure way of preserving a virtual machine configuration that you want to deploy many times.
When you clone a virtual machine or deploy a virtual machine from a template, the resulting cloned virtual machine is independent of the original virtual machine or template. Changes to the original virtual machine or template are not reflected in the cloned virtual machine, and changes to the cloned virtual machine are not reflected in the original virtual machine or template.