Ian Stirling wrote:

First, 'memory stick' is a (sony?) trademark, that is a type of removable
memory that is used by sony (and other products).

That's as may be, but that doesn't prevent the term being used
colloquially to refer to any type of solid state memory device which is
sort of stick shaped (or not, it's a free country). I work at an
educational establishment where these things are in widespread use and
most non-techies refer to them as memory sticks.

Probably explains why the term is not used much in advertising for
non-Sony products though :-)

Biggles