ext4

linux

Fourth extended filesystem — the default Linux filesystem, a journalling successor to ext3

Pronunciation

Correct

E-X-T-four

/iː ɛks tiː fɔː/

The letters 'ext' are spelled out individually, followed by 'four'. Most Linux practitioners say each letter then the number.

Source: www.kernel.org(official spec)

Accepted Variant

ekst-four

/ɛkst fɔː/

Some practitioners say 'ekst four', treating 'ext' as a syllable. Both forms are widely understood.