What is an ERC20 token?
ERC20 is an official protocol for proposing improvements to the Ethereum (ETH) network and can be understood as a standard for tokens that are created on the Ethereum blockchain. For example, many ICO tokens are ERC20 tokens. ICOs, or initial coin offerings, are fundraising events where companies raise funds for projects by selling digital tokens.
A traditional finance analogy would be IPOs, or initial public offerings. IPOs are when companies get listed on public stock exchanges