One great lens to use is TIME. Did you know you can search for results filtered by different time boundaries?
For example, if you want to get a sense for New Orleans, you could do the obvious web search [ New Orleans ] and get back decent results.
Now, to see different time-slices of search results, click on the "Show options..." button:
This shows you the Toolbelt. And down in the middle of the Toolbelt is a set of options for looking at search results in different slices of time.
Any Time is what you normally see on web search results. The results are the best out of ALL the web that Google could find.
Latest are the results that are just now coming into Google. That means they're mostly from social media postings (such as Twitter or other user feeds), but results also come in from news organizations.
Past 24 hours means just what you think. These are the best of the results posted during the last day.
And Specific date range lets you select a time over which you'd like to see the results. Here, I've put in the day before and the day after Katrina hit New Orleans in 2005.
This time-slice feature is great for searching for specific date topics (e.g., Katrina), but also useful for getting the sense of what's going on in and around the city.
For instance, if you search on [ New Orleans ] and click on the "Past 24 hours" button:
And you'll see what the current topics are for the city and what news outlets generate content repeatedly during the week. (Apparently, the local football team made it into the Superbowl!)
There's one other timeslicing feature to note. Farther down in the Toolbelt is the Timeline view option.
Which gives you a timeline view of New Orleans over time.
Obviously, the web didn't exist back at the time of that big peak in the 1860's, so what's going on?
Google has indexed a huge volume of newspapers, magazines and books from that era. Each article is tagged with an "about date" (meaning, this is the time that the article is about). Newspaper articles, for instance, always have a publication date--and this is what you're seeing here. Something major happened in the 1860s (but I'll leave it to you to figure out what that was), and you see it here.
On the chart you can see the peak of Katrina stories on the right hand side. That right-most peak is in 2005, when Katrina came through. Note that you can click on the timeline to drill down and see those time periods in more detail.
So if you want to understand a topic, consider looking at it through different times--Recent gives you the up-to-the-second news, while Timeline can give you a great historical perspective. All points in between are open for searching as well.