AND-OR-Invert Gates for Implementing Sum-of-Products Expressions

Most Boolean reductions result in a Product-of-Sums (POS) expression or a Sum-of-Products (SOP) expression.
The Sum-of-Products means the variables are ANDed to form a term and the terms are ORed. X = AB + CD.
The Product-of-Sums means the variables are ORed to form a term and the terms are ANDed. X = (A + B)(C + D)
AND-OR-Inverter gate combinations (AOI) are available in standard ICs and can be used to implement SOP expressions.
The 74LS54 is a commonly used AOI.
Programmable Logic Devices (PLDs) are available for larger and more complex functions than can be accomplished with an AOI.