Several times each year, Mercury's orbit appears to reverse. Today, it halts, and turns direct again, calming down some of the mix-ups and drama.
Because Mercury is the planet of communication, technology, business endeavors, and travel, when it is in its retrograde period, those matters can go a bit haywire.
The most turbulence can occur when it is slowing down and switching directions, like today. (Again... this is not actually happening to Mercury's orbit! It's from our perspective on Earth).
Like a car changing gears, the transition period can be the most chaotic.
Happily, after some possible kerfuffle during the period while it changes directions, our garbled communications, transportation, and tech should settle down as well. (Although the Uranus retrograde doesn't end until January 10, so some disruptions and missteps may persist, since Uranus is considered the "higher octave" of Mercury).