The question that newbies often
ask is what is a rock vs a mineral.
They are two entirely
Rock is what our planet's crust consists of - it is an essential component of the planet
It is solid and it consists
of minerals, other rock pieces, sometimes fossils, and
rarely, a mass of glass.
By definition, it is coherent,
which means it holds together and must be broken to be
separated into pieces; and as opposed to some minerals, it is
not manufactured like concrete or brick.
In a nonglassy rock (which are the most rocks), the grains are stuck
together either because they interlock with each other,
natural cement - mineral material that percipitates from water and
fills the space between grains.