By default to most non-mathematicians, algebra refers to the algebra of the real and complex numbers, including linear, polynomial, rational, logarithmic, and exponential expressions, functions, equations and inequalities, and systems of equations. This is the standard fare of pre-calculus mathematics in secondary education and in non-mathematical undergraduate education.
However, several of the early questions using the algebra tag were specifically about abstract algebra and it made sense to define a distinct tag for it.
Before proceeding to make a distinction by editing the tags, I thought it would be wiser to ask the community: Should the unmodified algebra tag be used by default to mean common real and complex algebra?