The MOC3020 is an optically Isolated Triac Driver Device, contains a GaAs infrared emitting diode and a light activated silicon bilateral switch, which functions like a triac.

MOC3021 Opto Triac Driver, Opto-isolator, Triac Driver output 400V peak. This is useful in 220V AC application where microcontroller should be isolated from AC main lines.
Manufacturer: Fairchild Semiconductor.

The MOC3011M is optically isolated triac driver device. This device contain a GaAs infrared emitting diode and a light activated silicon bilateral switch, which functions like a triac. It is designed for interfacing between electronic controls and power triacs to control resistive and inductive loads for 115 VAC (250-400V Peak) operations.

EL3021 Opto Triac Driver, Opto-isolator, Triac Driver output 400V peak. This is useful in 220V AC application where microcontroller should be isolated from AC main lines.
Manufacturer: Everlight Electronics Co Ltd.

MOC3041 6 Pin DIP Opto isolator triac driver with zero cross circuit. This is useful in 220V AC application where microcontroller should be isolated from AC main lines.

The MOC3083M consist of a GaAs infrared emitting diode optically coupled to a monolithic silicon detector performing the function of a zero voltage crossing bilateral triac driver.
They are designed for use with a discrete power triac in the interface of logic systems to equipment powered from 240 VAC lines, such as solid-state relays, industrial controls, motors, solenoids and consumer appliances, etc.
Brand: Fairchild Semiconductor