"It's about a faster, easier, richer experience - a better way to discover what's in your world," Chief executive Evan Williams said. "We want people to get more out of it in less time."
The new-look site is currently being rolled-out across the US. Once this is complete, web users in other countries will be able to start using the new site. However, if you can't wait, here's a visual tour of the features the new-look Twitter offers.
Twitter: The new home page
After logging into Twitter, the new home page makes its debut. The left side of the screen still contains your timeline, but with a different look. But the width of the right-hand pane is significantly larger. This is where many of the new features play out.
Twitter: Info about users
Click the right arrow on a person's tweet and Twitter reveals information about that tweet and the user.
NEXT PAGE: Expanded timeline
Twitter: Expand timelines
When viewing your feed, clicking the arrow icon to the right of any tweet expands that user's timeline onto the right half of the screen. Before, you had to navigate to that user's own page, leaving your feed behind.
The inclusion of retweets in a user's timeline can be enabled or disabled on a per-user basis.
NEXT PAGE: URLs
If a tweeted URL is recognised as containing an image or video, that media can be viewed on the right by clicking the media icon; clicking the left arrow then collapses this panel, changing the right pane back to its original look.
Twitter: Creating tweets
Tweets can be made from the box at the top of the timeline, or by clicking the pen icon (in the upper right) to get this pop-up window.
NEXT PAGE: @ replies
Twitter: @ replies
'@' replies cause a dialogue button to appear to the right; click it and the conversation expands onto the right half of the window.
When a text entry field is not highlighted, press the question mark key on your keyboard and a list of shortcuts appears.