There are several possible explanations as to why use the circle in your logos. Circles are seen everywhere in nature and our sky, from the moon to the sun, a satisfyingly pure and basic geometric structure, and can also express a sense of peace, equilibrium and belief.
Through its infinitely going line, circle gives a sense of perfection and continuity. They can also be used to endorse the physical characteristics of a product, in a 2D way. Circles vary widely in that they lack resilience, straight directions and form Angular shapes which convey a sense of protection, traditionalism, strength, etc.

However, if you are willing to buy logo, and confused about what shape should you choose for your emblem, this article would be really helpful to you.
Here are the 6 most famous brands that use circle beautifully and elegantly in their designs.
Pepsi:
Coke may be the best beverage in the world, but over the years, Pepsi has done pretty well. And it’s plain, classic, circle emblem is enduring.
The logo was first based on script lettering, but then in 1940, along with distinctive red, white and blue colouring, the CEO chose to insert this Wordmark on top of the bottle cap.
He inadvertently developed what would become the Pepsi logo by incorporating wavy lines that resembled a flag to display solidarity for the troops during the Second World War.

LG:
This one almost looks like a button you would hope to see on an electronic system by incorporating the letters LG. By using simple circular shape both the brand name and the abbreviation of the motto ‘Life’s good’ are used in a way that resembles a winking, smiling face. Created in 1995, to this day, this emblem has been doing wonders in the market place.

Nivea:
Created by pharmacist Carl Paul Beiersdorf in 1882, NIVEA is a German-based multinational skin and body care brand. Nivea Crème was first sold in 1925 in a distinctive blue tin, and the emblem has been surrounded by a circle that represents the outline of these famous tins after a redesign in 2013. It turned out to be a very clever move, the circular logo looks fantastic and invokes a feeling of nostalgia in individuals who have used Nivea throughout their lives.

Target:
If simplicity is the aim of logo design, then you can’t get a circle logo that is more effective than Target’s. The name of the US retail brand is perfectly mirrored in the bull’s eye-style graphic, and it also tells customers a subconscious story.

Pinterest:
Launched in 2010, by operating as a virtual pinboard for people’s favourite pictures, Pinterest became one of the internet’s largest brands. It was not the simplest idea to physically express, so the platform uses circular shape in such a way around a ‘P’ symbol, which turns the name’s first letter into a pin. This symbol, in conjunction with the expression ‘Pin it’, makes it immediately clear what you are meant to do.

Starbucks:
Established in 1971, Starbucks is now the popular and high priced coffee shop in the world, why would you buy a thing for such high price when you can buy it for less price from someone else? This is because of the branding scheme they run and the essential part of it is their emblem design. This symbol based on two-tailed mermaid is so popular that it can do all work alone and the need for words coffee or Starbucks is faded away.

Conclusion:
These were the 6 amazing use of circular shape logo designs. If you are starting a new business and planning to buy a logo, take inspiration from these above-mentioned uses of circular shapes and try them in your logo design.