In Shared Hosting, the complete Physical Server is configured as an Operating System and many IP’s but same Hard Disk and RAM shared for the users to run their websites. Here the user cannot have OS reboot option, less performance due to limited RAM, Malware can happen because another user’s also on the same server. The main advantage in Shared Hosting is Less Cost.
In Dedicated Servers, the completed physical server is configured for your business no one has control over it. you can reboot OS, increase RAM and Hard Disk, any OS can installable and you will have a complete backup of your data.But Migration of the complete server will take time, No malware activity because only you are going to access complete server.To make migration easy I will recommend taking Cloud VPS because in Cloud VPS data backup is stored in different clusters.No manual actions are required. Bud Cost is huge.
In Russian VPS or Virtual Private Server using virtualization concept, the physical server is divided into several virtual operating systems. So each user in the Russian VPS will have OS reboot option and hardware up gradation but to upgrade user need to use ticketing system extra time is needed this enable’s Less cost compared to dedicated servers for better performance and migration I will recommend to take Cloud VPS.