Reading list: What is the difference between CGI, VFX, and SFX?
CGI (Computer-Generated Imagery) means visuals made fully on a computer. Computer generated imagery is used to create characters, objects, and scenes that do not exist in real life. In a cgi film, most visuals are digitally created. Computer generated imagery in film is commonly used for fantasy scenes, creatures, and futuristic worlds. Simply, what is cgi in movies refers to visuals created using computer software.
VFX (Visual Effects) combines real video footage with digital elements. It includes CGI along with green screen work, background changes, and digital effects added after filming.
SFX (Special Effects) are real, physical effects done on set, such as real explosions, smoke, rain, or makeup effects.
Conclusion:
CGI creates digital visuals, VFX blends real footage with digital effects, and SFX uses real physical effects. Computer generated imagery in film helps filmmakers show scenes that cannot be filmed in real life.

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