In general, the hosting service level comes in four flavors (steps):
1. Shared Hosting
2. Managed Hosting
3. Shared Dedicated (semi-dedicated)
4. Dedicated and Cloud

Shared Hosting
(Cost Range Avg: $.99 to $4.95 /m)
Shared hosting is usually referred to when the hosting service provider put your hosted account into a server space without specific regard to the server’s load or bandwidth usage, or your specific site requirements. In some cases, I have seen a server hold over 1,100 domains hosted off of one shared IP address in this type of environment. And I’ve seen load averages in excess of 20 to 30 times over the servers capabilities. Additionally, backups are usually only performed once a month, and recovering a backup (if it is actually available) is usually accompanied by a hefty fee. If your site is doing well with traffic or your hosting video or lots of images, don’t be surprised if the host provider takes your site off-line (without any warning notice) for causing overages in load or bandwidth.
This hosting is well suited for individuals that are not looking to cover mission critical communication, and would not be harmed if the hosting server went offline for 24-48 hrs.

Managed Hosting
(Cost Range Avg: $9.95 to $24.95 /m)
The Managed Hosting environment is similar to Shared Hosting, in that you are hosted along-side other hosted accounts. The difference is that the server, and your specific site, is closely monitored for load and bandwidth usage to ensure that the performance is always near maximum capability and has a high availability. Backups may be more frequent, but will cost to recover if it is available.
This level suits most business minded individuals and some small businesses that have performance needs greater than the Shared Hosting environment.

Shared Dedicated (semi-dedicated)
(Cost Range Avg: $24.95 to $79.95 /m)
The Shared Dedicated environment is similar to Managed Hosting, in that you are hosted along-side other hosted accounts and you are managed. However, with shared dedicated the environment only allows for a select group of hosted accounts and is much tighter for performance load and bandwidth. The server, and your specific site, is closely monitored for load and bandwidth usage to ensure that the performance is always near maximum capability and has a high availability. Backups are managed on a regular bases. And in some cases, the server is configured in a load-balance redundancy environment. This means that equipment failures are not noticeable, and the host service provider can claim a 99.9% up-time on a specific configuration.

Dedicated
(Cost Range Avg: $179.95 to $459.95+ /m)
Dedicate Hosting is just as it sounds. There is a dedicated server that is devoted to your hosted needs. Dediated servers are usually geared toward businesses that have IT staff to configure and manage the environment.

Cloud Hosting
(Cost Range Avg: $179.95 to $459.95+ /m)
Cloud Hosting is very similar to Dedicated Hosting, except the correct terms to use would be – there is a dedicated amount of server resources devoted to your hosted needs. The Cloud environment is usually comprised of a cluster of load balanced servers. And, you purchase the number of processors and ram that you would like devoted to your hosting needs. Like Dedicated Hosting, Cloud Hosting is usually geared toward businesses that have IT staff to configure and manage the environment.

Managed Dedicated
(Cost Range Avg: $359.95 to $859.95+ /m)
Managed Dedicate Hosting is similar to Dedicated and Cloud Hosting however, the server is managed for updates, load, bandwidth performance. Basically, think of this level as getting hosting with an IT Contractor on staff to make sure that the server is performing properly.

All of the services above that contain the word “Managed” in them indicate that there is an IT Support Staff assigned to the server (or cluster) to respond to issues the server may have. The “covered” services are usually limited to performance load and bandwidth issues. As a result, if the servers are performing as they should, any request for support that doesn’t pertain to performance load or bandwidth is usually billed at a competitive rate ($60-$250/hr).

Lastly, even though there may be instances when you may need to recover a past version of your hosted space (site or email), there have been many more instances when a host provider recovered equipment from a hardware failure, but didn’t retain backups to recover the hosted accounts to the most recent state. So, for your needs, as well as the host provider’s needs, make sure what you are aware of the backup policy of the service level you choose.
Here is an extended read about Pinion Media/MHz Web Hosting Server Backup Policy.