ERC-20 refers to the Ethereum coin standard. The standard is used for the implementation of tokens. It is governed by a common list of rules that defines interactions between tokens that include transfer between addresses and data access.
ERC-20 is considered to be the one of the most significant tokens. It had emerged as the technical standard for smart contracts within the Ethereum Blockchain upon implementation of tokens.
There are a number of popular cryptocurrencies that use the ERC-20 standard, these include Maker (MKR), Basic Attention Token (BAT), Augur, (REP) and OmiseGO (OMG).