All planets (except the Sun and Moon) go retrograde some of the time. When Mercury goes retrograde, usually 3 times a year, it's an opportunity to take some time out to catch up on forgotten tasks and review decisions and plans.
All planets (except the Sun and Moon) go retrograde some of the time. Retrograde means the planet appears to go backwards, and means that the planet's energy is internalised, intense and often difficult to express outwardly.
Mercury retrograde is special for a couple of reasons. For one thing, Mercury is our conscious mind and communication, and therefore it can intimately affect how we think and perceive and express ourselves. Also, Mercury goes retrograde about 3 times per year — more often than any other planet. Mercury goes retrograde for about 3-3½ weeks at a time, and the overall cycle (including the Shadow period) extends over almost 2 months.
Mercury retrograde is typically a time when it is necessary to rethink, rehash and reflect, and it is common for new information to emerge later in the retrograde cycle that you didn't anticipate (but wish you had!) Because of this, it is advisable to avoid making final, permanent decisions (e.g., signing contracts) during this time, but it is an excellent time to do your homework and research in preparation for major decisions.
On the other hand, life must go on and things can't always be put on hold for that long! The Mercury retrograde dance can also be seen as a natural part of a trial-and-error process, in which you take one step forward, see what the result is, and then step back to rethink your actions.
The important thing is not to paint yourself into a corner by making final decisions that can't be changed later without creating serious problems. Try to build in some flexibility, so that you can adjust your gameplan later, as new information is revealed.