What shortcut can I use to create fields in my ruby code?

In this video: at 3:24, the narrator types in field, then hits something on his keyboard to automatically generate the fields.

What keyboard shortcut is this and how can I replicate it?

Wal-Mart Cyber Monday online sales break record

Wal-Mart on Tuesday announced that online sales broke company records, with more than 1.5 billion pages viewed between Thanksgiving and Cyber Monday.