Fishman's extended definition
H (High) variety: Modern Standard Arabic (MSA) :used in government, education, media, and religious settings.
L (Low) variety: Algerian Arabic (Darija) : used in daily conversation, home, and informal contexts.
Key Fishman criteria met:
1/ Functional complementarity (H and L serve distinct, non-overlapping domains).
2/ Prestige (H is idealized, L is stigmatized).
3/ Acquisition (L is native, H is learned through schooling).
Important nuance: Fishman’s model allows different languages, so Algeria also shows an extended diglossia where French acts as another H variety in science, business, and higher education—competing with MSA.