As you work with Q#, Pauli measurements are a common kind of measurement, which generalize computational basis measurements to include measurements in other bases and of parity between different qubits. In such cases, it is common to discuss measuring a Pauli operator, in general an operator such as X,Y,Z or Z⊗Z,X⊗X,X⊗Y, and so forth.
Discussing measurement in terms of Pauli operators is especially common in the subfield of quantum error correction.
Q# guide follows a similar convention; this article explains this alternative view of measurements.
