Media buying is a process used in paid marketing efforts. The goal is to identify and purchase ad space on channels that are relevant to the target audience at the optimal time, for the least amount of money.
With media buying, you can place ads about your company, services, or products on websites where competitor ads are found.
If ads are consistently running, your brand's name will become more common amongst the targeted audience. Additionally, this increases the chances of people buying your services/ products.