ETrade Core Portfolios are a type of robo-advisor service. Robo-advisors are automated investment services that use algorithms to build and manage investment portfolios. They are designed for investors who want to invest in a diversified portfolio of stocks, bonds, and ETFs but don't have the time or expertise to do it themselves. If you don't have the time or expertise to manage your own investments, then ETrade Core Portfolios can be a good option.