Chicago time explained
Chicago keeps Central Time, one hour behind New York and two ahead of Los Angeles, changing clocks on the same dates as the rest of the country. Central is the second most populous US zone and covers a broad swathe from the Gulf coast to the Canadian border.
Chicago does observe daylight saving, so its offset from UTC changes twice a year. The time above already accounts for whichever is currently in force.
Reaching Chicago
Chicago sits between the coasts, which makes it the easiest large American city to schedule from — New York is an hour away and Los Angeles two, so a mid-morning call reaches both.
How this page works
The time above is calculated on your own device from the IANA time zone
database that ships with your browser, using the zone
America/Chicago. Nothing is fetched from a server, and the offset
shown is whatever is currently in force rather than a
number typed into the page — so when a country changes its rules, this
page changes with it.
The difference from your own clock is worked out the same way, comparing Chicago's current offset against your device's. If your computer's clock is wrong, so is that comparison.