e107 is a cms written in PHP and using the popular MySql database for storage.
It isa fact that novadays it is not enough to "be in the internet", if you are running a website for your busines or organisation, there will always be competitors. You can of course hire a web designer, a seo, agraphical artist to develop the best site ever. Can you afford the rates? Can you quickly change something on your site?
I doubt, using a cms like e107 you can quickly change content on your site, assured that your layout is not changed. This way visitors and search engines will find what they want.
What makes e107 special is the way it works, it comes with a selection of ready made templates, called theme, it has almost everything realised as plugins, giving your site a clear structure.
Changes and additions to the core are easy.
For a usual business onrientated site you dont have to change anything, just upload the cms to your server, fill the site with good keyword rich content and find some links, you will in most cases rank better than your competitors. Google and co are loving good structured sites, e107 sites are.
If you are in a higher competive market, it will be a good advice to build your e107 in close contact to your search engine optimization specialist or let him do the work.
But you will for sure have your site developed in less time for less money than if you do it the "classic way".