The projective general linear group 
is the group obtained from
the general linear group 
on factoring by the scalar matrices
contained in that group.
Projective General Linear Group
See also
General Linear Group, Projective General Orthogonal Group, Projective General Unitary GroupExplore with Wolfram|Alpha
References
Conway, J. H.; Curtis, R. T.; Norton, S. P.; Parker, R. A.; and Wilson, R. A. "The Groups
, 
, 
, and 
." §2.1 in Atlas
of Finite Groups: Maximal Subgroups and Ordinary Characters for Simple Groups.
Oxford, England: Clarendon Press, p. x, 1985.Referenced on Wolfram|Alpha
Projective General Linear GroupCite this as:
Weisstein, Eric W. "Projective General Linear Group." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/ProjectiveGeneralLinearGroup.html