Web hosting is a monthly fee that you pay to have your site physically stored on a web server which makes your site accessible on the Internet.
Kimberley Web Design can help you through the signing up process and make recommendations as to the best value for money. Often for a small business, the least expensive package is sufficient.
Hosting companies require that you own your domain in order to host with them and it is often good practice to obtain hosting and domain registration with the same company.
Most hosting companies employ technical engineers to make sure your website is always available and support staff for when website owners are in need of help. They also provide free email services.