Spending money on ad network like Facebook ads, Google AdWords ..ect are and deriving traffic to your website is meant to be paid traffic.
The counter part of paid traffic is organic traffic which can be achieved only by optimizing your site using SEO strategies.
Paid vs Organic
Paid marketing(traffic) is done to achieve a goal in short time duration whereas Organic can not be achieved in a day or week it will take some months or even years. If you achieve success in organic traffic then advertise using Paid marketing method can derive you more conversion comparatively. And also organic traffic will give you long time benifites without money. This can be achieved by SEO and SMO .Organic will consume large amount of time and human resources. But you have a budget and knowledge in advertising you can achieve in paid marketing.
I’ll suggest achieving Organic traffic before any kind of paid marketing is the best marketing practice to achieve your goal.