The full form of "computer" is most commonly cited as:

• Common Operating Machine Particularly Used for Technological and Educational Research1234

Alternate versions exist with slight wording changes, such as "Commonly Operated Machine Particularly Used for Technical and Educational Research" or "Common Operating Machine Purposely Used for Technological Educational Research"1234.

It's important to note that this full form is not officially recognized in the field of computer science—"computer" is not originally an acronym, but over time, expanded forms like these have become popular in educational circles2.

Summary table:

The commonly taught full forms are useful as mnemonics, but in technical contexts, "computer" simply refers to a programmable electronic device that processes data5.