Most hosting companies manage large numbers of website computers called web servers. When you have your website hosted by a HC you will usually pick, between one of four plans: shared, virtual private, cloud and dedicated. Most small businesses with small websites will do just fine with a shared plan. A shared plan just means that your website shares one server with a handful of other websites. This is because, unless you have a very large site with a lot of visitors, you do not need all the resources that the server has to offer. Therefore, the HC assigns enough websites to a server to use up most of its available resources (multiple CPUs, memory, processor speed, disk space, etc).
When you purchase a hosting plan the HC gives you an account to manage one domain which will have one website. This account allows you to manage email accounts, FTP accounts, file managers, backup managers, domain managers, upgrade options, promotional options, statistics options, security options, database tools, software services, preferences and advanced services. Using most of these managers, options and services will require some degree of knowledge on how to use them correctly and wisely and using most of these incorrectly can potentially cause a range, from small to large, of problems with your website. So it is best to leave the management and maintenance of your hosting site to a professional web master.
One very important area of maintenance is the regular downloading of complete backups of your entire website. Most website owners can be taught how to do this - it is not difficult. You need to do this regularly if (1) you make regular changes to your website or (2) if your website CMS uses a database to store website information and visitor information. These backups will allow you to recreate your website should something bad happen to the HC server causing your website to be corrupted or lost.
A major area to be aware of for CMS maintenance is upgrades. There will be upgrades for every piece of software listed above and these upgrades become available at different times. Many upgrades fix known bugs in the software, others add new functionality. Decisions as to whether or not to upgrade constantly need to be evaluated and if upgrading is desired then performing the upgrade. From time to time upgrading causes small or large parts of your website to "break" and changes will have to be made at either the editing level, the design level or the developer level.
Static, unchanging, websites usually don't invite repeat visits. Consistently having out of date information on your website is one of the fastest ways to kill visitor traffic to your website. You will need to determine what amount of upkeep your website will need to retain your current visitors and increasing the arrival of new visitors. You have to think of ways to keep your site "fresh" and "alive" with minimal maintenance. Here is a list of things that you can do to keep your site appealing for repeat visits.
Some of these items will need the help of a web master to do but others items, like a blog or keeping the product information up to date, can be maintained by you as the website owner.