Answer
Cyber libel is libel committed through a computer system. Section 4(c)(4) of the Cybercrime Prevention Act (Republic Act No. 10175) adopts the definition of libel in Article 355 of the Revised Penal Code and applies it to acts done online — for example through social media, websites, or messaging.
Because it borrows the Revised Penal Code definition, the underlying offense is still libel under Article 353: a public and malicious imputation of a crime, vice, defect, act, or condition that tends to dishonor or discredit a person. The distinguishing feature is only that it was committed through a computer system.
Sources & further reading
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