Old advert number

[GMH]

Watching clips of old adverts from the 1980s on You Tube, I noticed that a lot of companies used the same telephone number - 01 200 0200 if you needed to contact them, to ask for example, where your nearest Allied Carpets is. If you dialed that number back then what kind of service would you have got through to? Was it a bit like the 100 operator's service, who would put you through to the service of the company you require, and is the eqivilent of that old "01" number still going today?