MARK / SYMBOL: An identifying mark or symbol that doesn’t contain the business name. For example, the Instagram icon ⟶
A logo is a graphic mark, emblem, symbol or stylized name used to identify a company, organization, product, or brand. It may take the form of an abstract or figurative design, or it may present as a stylized version of the company’s name if it has sufficient brand recognition. Logos have become an integral part of a company's brand identities. A widely and instantly recognized logo is a valuable intangible asset for a corporation and is thus trademarked for intellectual property protection, in the majority of situations.
—Logos by Will Kenton in Investopedia