Hi @Karen Margrave
That is a great question! The word "website" is about as broad a placeholder as the word "real estate". It basically covers anything and everything that displays content for a user to interact with via a screen (and sometimes beyond that). When you are looking for solution to drive new business, establish credibility with prospects, share case studies and examples, and encourage the right people to contact you, there are a couple of approaches (in order of labor involved):
The Landscape
1) Software as a service (example: wordpress.com, wix.com, squarespace.com ...)
These are companies that have pre-build and hosted solutions to make your life easy. They are all quite good and affordable. What they are not is extremely flexible.
2) Self hosted open-source solutions (WordPress, Joomla, Drupal...)
These are free software platforms that communities have created to make managing websites user friendly. You can host your own version cheaply on a server like dreamhost, wp-engine or digital ocean. The advantage of doing it yourself as opposed to a saas (see #1) is that you can customize they to do a number of unique things the saas providers may not offer
3) Custom builds
Up until 10 years ago, all websites were custom. Today, I wouldn't advise it in your situation. Too costly, and overkill.
Choosing:
I would suggest the following approach: make a list of all the things your website needs to be able to do. For example:
* Custom domain (http://www.parlayinvestments.com)
* Gallery
* Contact us form
...
Then explore the SaaS solutions to see if they do everything you need. If that works, then go with the one you like best. If you find yourself limited, then go with self hosted. I wouldn't waste my time trying to figure out how to do it yourself, just hire a freelancer (elance, microslancer...)
WordPress
You asked some specific WordPress questions. WordPress is a free open source platform to allow people to make blogs & websites (wordpress.org). That is separate from the freemium service offered at wordpress.com. A WordPress site is composed of three elements: WordPress (core) + Theme (visual) + Plugins (additional functionality). The SaaS service organize the workflow of choosing for you. If you do self hosted, typically you will go to either the free repo (http://wordpress.org/themes/) or to a commercial marketplace (http://themeforest.net/category/wordpress or https://creativemarket.com/themes/wordpress) and pick a visual layout you like. Then you will decide what functionality you need and choose the appropriate plugins. For example, if you needed an event calendar (http://wordpress.org/plugins/the-events-calendar/) or a newsletter (http://wordpress.org/plugins/wysija-newsletters/). WordPress is great for running a blog @Douglas Dowell mentioned as well as a full scale website.
We have used WordPress to power some of the world's largest sites and communities for companies like Microsoft to Bon App