Final answer:
DNA microarrays can be used to compare gene expression patterns between different samples, such as infected and uninfected cells or cancerous and healthy cells.
Step-by-step explanation:
Microarray technology is used to compare gene expression patterns between different samples. It involves immobilizing DNA or cDNA fragments on a chip or slide, labeling them with different fluorescent dyes, and then comparing the sequences or patterns of gene expression. This technology is commonly used in research settings to study the effects of infections, chemical treatments, or diseases like cancer on gene expression.