The 2N2222 is a widely-used NPN bipolar junction transistor (BJT) with a TO-92 package. It is a general-purpose transistor that can be used in a variety of switching and amplifier applications. The 2N2222 has a collector current rating of 600 mA and a collector-emitter voltage rating of 40V, making it suitable for use in a wide range of circuits. It is commonly used in low-power switching applications and can be used as a switch or amplifier in circuits that require a small amount of current. The 2N2222 is a popular choice for use in DIY electronics projects and is a useful component for any electronics enthusiast or professional.

The 2N2222 is a common NPN bipolar junction transistor (BJT) used for general purpose low-power amplifying or switching applications. It is designed for low to medium current, low power, medium voltage, and can operate at moderately high speeds. 

The 2N2222 is considered a very common transistor, and is used as an exemplar of an NPN transistor. It is frequently used as a small-signal transistor, and it remains a small general purpose transistor of enduring popularity.