This is the tendency to find patterns that aren't there, making meaningful connections between unrelated things. This distorts our sense of reality and shifts us into a realm where everything becomes infused with meaning.
It can be a normal process or an abnormal one. Everyone finds patterns that aren't there. Our brains are wired to seek patterns. Paranoid schizophrenia is an example of abnormal apophenia where too many connections become delusional.
This phenomena is closely linked to pareidolia, but is more concerned with all information.
It's another reason why we our perception cannot be trusted.