In choosing which media to consume on a regular basis, most people prefer to live within their own political comfort zones. They read and view news outlets that reinforce their own prejudices.
A study by the US-based Pew Research Centre, "Political polarisation and media habits", shows that, in America, "liberals and conservatives inhabit different worlds".
It finds that the group it identifies as "consistent conservatives" favour a single news source, which is - surprise, surprise - Fox News.
Some 47% cite Rupert Murdoch's "fair and balanced" Fox News as their main source for information about government and politics, and 88% of them say they trust what they see and hear.
By contrast, those with consistently liberal views "are less unified in their media loyalty" because they use a wider range of news outlets. And they are less likely to trust what they read and view.
The Pew report concedes that "it is virtually impossible to live in an ideological bubble" because "conservatives and liberals hear dissenting political views in their everyday lives."
Yet it also argues that at the extremes - the 20% who are consistently on the left and right ends of the spectrum - "have a greater impact on the political process than do those with more mixed ideological views."
They are the most likely to vote, to donate to campaigns and to participate directly in politics.
As for social media, the report suggests that consistent conservatives seek out political opinions that reinforce their views. They "are twice as likely as the typical Facebook user to see political opinions on Facebook that are mostly in line with their own views."
Consistent liberals, who generally access a wider range of views on social media, do not, of course, embrace such views. But 44% of liberals on Facebook say they have blocked or defriended someone because they disagreed with something that person posted about politics.
This compares with 31% of consistent conservatives and just 26% of all Facebook users who have done the same.
There's much more to discover in the Pew report. To read it all go here.
