The Pleiadians seems beside the Zeta-Reticulis one of the well-known cultures who interact with humankind here. There are many reasons, my personal view you find in RKMCorner.
There are different understandings of the Pleiadians, the one I perceive is: they are Dimension Travellers and guardians of the gates you pass when you leave or enter some dimensional planes.
Their main approach is handling time/space possibilities, and one expression of this knowledge is the technology, which allows them to travel and shift dimensions to each other, to allow inter-cultural exchange of spiritual-knowledge.
Pleiades--in the constellation Taurus (the bull)--an open cluster of newly forming stars with bluish-gas glowing around them from which the stars were formed. (Also called the 7 sisters) They are about 400 light-years distant. They are visible in the evening sky in the northern hemisphere from mid-October to March.