It depends on if you're speaking British or American English.The British pronounce it as "istory," so they use "an" before.
dataflow · · focus · HN ↗
beaned · · focus · HN ↗
The British pronounce it as "istory," so they use "an" before.
Planktonne · · focus · HN ↗
fsckboy · · focus · HN ↗