In August, Hurricane Katrina breaches New Orleans' levees and leads to massive flooding, killing more than 1,800 people and displacing hundreds of thousands more. In February, the New England Patriots win their second Superbowl victory against the Philadelphia Eagles, and a video uploading site called YouTube is founded.
Meanwhile, in music, Gwen Stefani lets the world know she ain't no "Hollaback Girl" (whatever that is), 50 Cent makes sure we could never look at a lollipop the same way again with "Candy Shop," and Mariah Carey makes a comeback with her album The Emancipation of Mimi.
Revisit all of 2005's biggest hits with a full list of the Hot 100 chart-toppers here:
Mario, "Let Me Love You"
This Grammy-nominated song from the R&B singer's second studio album proves to be an instant hit. Written by Ne-Yo and laced with the keyboard riffs from Tina Turner's "What's Love Got To Do With It," "Let Me Love You" tops the charts solidifying its place as the slow-dance jam of 2005.
50 Cent feat. Olivia, "Candy Shop"
A racier and more innuendo-filled departure from the previous No. 1, 50 Cent's "Candy Shop" sits at the top of the Hot 100 after knocking Mario out of the top spot while featuring the sultry vocals from R&B singer Olivia.
Gwen Stefani, "Hollaback Girl"
The song that spawned many perplexed musings over just what a "Hollaback Girl" is, Stefani's hip hop-influenced single from her debut solo album Love. Angel. Music. Baby. nonetheless hits the top of the chart. Despite the mystery, the single earns the former No Doubt frontwoman two Grammy nominations, including Best Female Pop Vocal Performance.
Mariah Carey, "We Belong Together"
The second single from Carey's tenth studio album The Emancipation of Mimi, "We Belong Together" is often described by critics as the song that saved the R&B singer's career.
Carrie Underwood, "Inside Your Heaven"
Fourth-season American Idol winner Carrie Underwood's debut single earns the singer a Billboard Music Award for top-selling country single of the year.
Kanye West feat. Jamie Foxx, "Gold Digger"
The second single from the Chicago-born rapper's second album Late Registration, "Gold Digger" features actor/singer Foxx singing a sample of Ray Charles' "I Got a Woman." The song warns America about the dangers of falling for a gold-digger, even though he's not sayin' you're a gold-digger.
?Chris Brown, "Run It!"
The now-controversial hip hop artist's debut single launches then-16-year-old Brown into the public eye.
Mariah Carey, "Don't Forget About Us"
The fifth single from Carey's The Emancipation of Mimi tops the charts during the last week of 2005, becoming the second chart-topper that year for the singer.