E-1 and E-2 visas are for Traders and Investors, and allow the foreign national to engage in trade or investment services or activities in the U.S. provided there exists a treaty between the U.S. and the foreign national’s country of citizenship. See https://travel.state.gov/content/visas/en/fees/treaty.html
Specifically, E-1 (Treaty Trader) visas are for people who own or work for companies that do a substantial amount of trade with the United States, and who will be working for that company in the United States for an extended period of time. E-1 visa applicants must establish to the satisfaction of the consular officer that their company carries on well-established and significant trade in goods and/or services between the treaty country and the United States.
E-2 (Treaty Investor) visas are for people who personally invest a substantial amount of their own money in ventures within the United States. These visas can only be issued if the U.S. has a treaty with the alien's country.
Major foreign companies that establish a presence in the United States generally qualify for E-2 status. This status provides an excellent vehicle for easily bringing in foreign workers who have the same nationality as the foreign base company. Also, unlike the L-1 status which requires at least one year of prior employment with the foreign entity, E beneficiaries can be new hires.