VPN - Virtual Private Network is used to connect your computer to the company's network.
For example, let's say in your company, you have a storage hard drive @ 172.168.1.1
Now this IP, is a private IP and cannot be accessed over the internet. Only systems which are there on the company's network can access it.
Having said that, if you want to access this storage device from your home, you will have to connect to your company's network through VPN. And once you are connected, you will be able to access this storage device.
Cloud on the other hand is different. In Cloud also, you can have private resources and public resources.
If there are any private resources on the cloud, you still will only be able to access it through VPN.
Cloud basically gives you resources, which the company does not have to buy. The company can rent infrastructure from cloud and use them as their own.
Hope this answers your query.
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