The overall meaning of promotion is similar to advertisement but slightly different. Advertisement is an aspect of Promotion. Promotion is broadcasting a product/service to a public audience using pure content. It's about putting more personal thought into your content before promoting it. Advertisement also require a well-thought process but it's a commercial thought process because the user has to think from a audience point of view to make an sale. Promotion is a organic way to connect with the audience/customers and the most efficient way to build a brand.
Difference between Advertisement and Promotion.
As I explained one major difference between Promotion and Advertisement in the paragraph above, I realize another major factor between the two. When running a promotion, there is little to no cost compared to a advertisement campaign. Promotion is more for the loyal audience and advertisement is a tactic to gain new audience. That's why the ROI (return on investment) is important when running ads on social platforms because it's considered advertisement. The ROI don't too much matters when using organic promotion.
Why Promotion is Important?
As a digital marketer, I believe organic promotion is mandatory when it comes to marketing. It's always best to have a genuine connection with the audience because it builds trust within the brand and audience. Once the trust is built, that's how some of the audience becomes paying customers. Not just any paying customers, the "loyal" paying customers. Which means the customers will buy naturally just because they want to support your brand.
Being able to connect with the people more personally is the biggest importance of promotion. Promotion will increase a companies sales higher than the expectations was before. The more often the people see's the company promotion, higher possibility of them engaging with the content. Engagement is a result you'll get after a successful promotion campaign, and engagement is a step closer to a sale. So without that promotion, it raise the difficulty of increasing the content's conversion rate.