When you have a website finished, do not expect it to automatically be available on the Internet. You need a hosting service to make that happen. That is a large shared server. The service is sold to website developers and you can use it along with the other customers. The server itself is huge and contains sites from all over the world. You purchase the right to put yours on through the service. You may find a hostgator coupon that will have a good price offer for new customers.
Decide whether you want a live support system or not. This can be an online chat or telephone support. Some hosting services offer information to read and tutorials online but no live assistance. You will also want to know about downtime.
It is wise to know how much downtime the service allows itself each month. Downtime means the time that the server is not keeping your website live on the Internet. If there is a specified time, ask if random unexpected downtimes are included in the total. You do not want your website unavailable for a large share of the time you are paying for.