A fiber optic SFP module is a compact, hot pluggable optical module used to connect network devices such as switches, routers, and servers through optical fiber. It enables data transmission over long distances with high speed, stability, and minimal signal loss. Sometimes, it is known as the mini-GBIC (gigabit interface converter) or SFP transceiver. However, some technicians may also mistype it as an SPF module, which is the same. This article provides a comprehensive comparison of mainstream optical transceivers, including SFP, SFP+, QSFP+, QSFP28, and QSFP-DD.