Synchronicity. What is synchronicity? It's events that seem to be connected, but there is no actual connection or cause this concept was thought up by psychologists Carl Jung. Most people will call this a coincidence. What it could be is the universe or even your higher self trying to get your attention. Here are some examples of synchronicity to give you a good idea, we all experience it in our own way.
One, you are thinking about someone and they suddenly call to you keep having the same kind of experience. For example, always seeing puppies, you see them outside on TV, etc. This could be a signal to pay attention and adopt a pet. It can go in a negative way to maybe you keep bumping into people that are angry. This could be your higher self telling you to work on your anger issues. If you keep going through the same bad stuff.
The universe or your higher self is trying to get you to learn the lesson. Three number sequences, do you always see a pattern of numbers? Personally, I always see two, two or 222 1111. But I used to always see 616 it's different for everyone. If you have an interest in numerology, you could look it up to find the meanings. It could also be your higher self nudging you to pay attention.
Stop and look around you when this happens. What are you doing when these numbers pop up? How are you feeling? Who are you with? You can find answers this way. For dreams, a reoccurring dream is a message to pay attention to something prophetic dreams, a dream you have that comes into reality.
I have had this happen twice. I dreamt how a boy would break up with me in high school and it happened that week. Later in my adult life. I was dreaming that my friend's ex girlfriend called him and asked him if he would like to meet his son who had been born a month prior. I woke up from that dream to my friend's phone ringing and it was his ex, asking him that very question. I was blown away by it.
Synchronicity is the inner world manifesting in the outer world. Most of the time when you experience a coincidence, it is probably synchronicity. It's our higher self trying to get our attention to lead us in the direction that our soul wanted to go in this life.