Starting Thursday night, there are many parties ranging from room parties to frat parties to organized campus-wide dances. The room and frat parties are pretty much comprised of people densely crowded around a warm keg listening to Lady Gaga, similar to what you'd find at many colleges. You can frequent these until you graduate (free alcohol?), but most students choose to mix up their social life with theater performances, college-sponsored dances with live DJs, comedy shows, a cappella jams with afterparties, and intimite wine and cheese parties.
While frats can be moderately fun at best, Yale is known for its campus-wide parties sponsored by organizations or residential colleges. Themes such as Prohibition, Trolley Night (Mardi Gras), Safety Dance, and seasonal dances abound. Cultural organizations such as the African American house host events and the Lesbian/Gay/Bisexual/Transgender Co-Op holds several dances a year (for both straight and gay students) that draw a crowd.
As for bars and clubs, students are generally limited to places near campus, most notably Toad’s Place. Toad’s has Yale party nights with free drinks and free admission, and sometimes it offers student discounts for concerts.
Overall, Yale's hallmark holds true for nightlife. There is an abundance of anything and everything and it's up to you how you spend your evenings. Whether chilling at a wine and cheese party with your closest friends or owning the dance floor at Toad's, you'll be sure to have a variety of options and opportunities.