COVID-19 and its spread points to some different trends. We're seeing more positive cases, partially but not fully due to a lot more testing, yet overall hospitalization rates and deaths from Covid have generally declined or remained within a consistent range. Yet, with the spread of cases, additional precautions are underway in communities all over. Many stores, including large chains like Wal-Mart, Kroger stores (including Pick N Saves), Menards, and more are requiring masks to enter their stores; many restaurants are asking customers to wear masks everywhere inside except when eating and drinking at their tables.
But a mask is useless unless it actually offers protection, right? Cloth or fabric masks are currently recommended by the World Health Organization and the CDC for the general public, but the thread count and tightness of the weaves in any cloth-based mask makes a huge difference in its level of effectiveness. The N95 masks, which doctors, nurses, EMTs, and other front-line workers use is the most effective and directly blocks the virus itself because the protection level filters down to such a small level.
The virus itself - technically called SARS-CoV-2 - is very tiny; about 0.1 microns in size. However, the virus is almost always attached to something larger, or embedded inside a droplet, such as a drop from a sneeze or cough. That means in most cases, most masks - including tightly-woven cloth ones - will provide ample protection. But really, if you practice social distancing and spend more time outdoors, you're much better off regardless of your mask size.
This piece from Business Insider offers a comprehensive look at masks and the levels of protection they offer. It's pretty useful as you gauge the level of protection (plus price, availability, etc.) you're looking for.