They also used to offer webhosting if you were subscribed to them and would never delete your website even if your contract expired (I've got an ugly one from 2006 that's still up even though I've changed ISPs a while ago).
And the subscription itself was free for their RTC per-hour plan, hence the name.
It means it was one of the most popular web host in France during that time, it was literally free, with decent space for the time (upped over time, I think it started at 100MB to 10GB now), a MySQL database, PHP support, no ads, no weirdness. You didn't even have to use that RTC plan you subscribed to.