MIX10: Designing Bing with Heart & Science

by Luke Wroblewski March 16, 2010

In his Designing Bing: Heart & Science presentation at Microsoft's MIX10 conference, Paul Ray talked about the design process behind Microsoft's new search engine, Bing, including how the team uses data and design principles to make decisions.

  • Microsoft started building their own search engine six years ago. Named MSN Search then Windows Live Search then Live Search (2006-2008) and now Bing (summer 2008)
  • Bing targeted features to “explorers”. Explorers represent 25% of all searchers and 30% of all searches in US at the time. They are people willing to try new technology, who like surprises, often get sidetracked from their original intent, and frequently dig deeper into results.
  • Bing’s Mission: deliver great results, richer more organized experience, and help accomplish key tasks more easily.

Design principles for Bing:

  • Design for explorers
  • Delight and surprise our users
  • Earn Trust
  • Be the brand
  • Make money
  • Showcase our best
  • Organize the page by relevance
  • Respect the need for speed
  • Give just enough and offer more
  • Present a seamless experience

Design problems needed to get solved:

  • Highlight the big bets
  • Rationalize refinements
  • Readability & scanning
  • Encouraging exploration
  • Pass the over the shoulder test

Data Driven Process

  • Bing’s big bet was on categorized search: organize results into categories that make sense. This was an untapped need in the market.
  • Early explorations for Bing focused on faceted results and a tab-based UI for category filtering. As you might expect, they were placed at top, left, and right in design explorations.
  • A/B Testing: colors & typography, ads, performance, answers, more content (groups). Impact to revenue, return rate, time to first click, whole page CTR, etc. help make decisions.
  • Guess what? Microsoft also tested multiple versions of blue for links in their search results. A specific color of blue (#0044CC) drove $80-$100 million dollars a year increase over the light blue the design team tried first.
  • Tested calling out answers with a text indent and a small graphic at the top of a search results page but making these look more like actual search results resulted in much more engagement.
  • Does performance matter? User engagement dropped significantly even with only a 1 second delay. A 2 second delay doubled all the bad metrics.
  • Load the page progressively, show results first, then lazy load the rest.
  • Eye tracking showed that categories on the left side of the page got 11% fixation vs. 2% fixation on the right. Since categories were a big bet for Bing –they needed more attention so are on the left.
  • Instrumentation & Analytics –everything is measured. Also use user research, usability, etc.
  • Large images on Bing home page were popular with users but added a lot of page weight. Team had to develop a lazy load solution to pull up the search box right away.
  • More successful images on Bing home page are natural wonders. Composition of photos is important –the search box needs to be strongly visible.

Homepage design principles

  • Enhance, don’t hinder search
  • Preserve user’s trust
  • Be artful, not newsy
  • Strive for subtlety and poetry