There is no business without competition. Why do I think that? If there is a real problem you address, there is, for sure, someone of your potential customers is also trying to solve the problem. In most cases, this will be a product of a competitor of yours.
On your competition slide, you list all major competitors in your market and describe what they do well and what they do poorly. Additionally, you show what distinguishes you from these competitors and where you see your position in the market compared to your competitors. The competition slide is also an excellent place to present your competitive advantages (also called USPs).
There are three popular graphics that most founders choose from for their competition slide. The first one is a graph, in which the essential aspects of your product label the x and y axes (e.g., Cost & Value). The second one is a comparison of the most important product features, and the third one is a cluster in which founders portray the market, including you and your competitors.