Hash key

[Brum1]

The Hash key has been a feature on all telephones since the dail disapeared. It is only fairly recently that the key has been used on a phone.
So my question is...For what original reason was the Hash key put on our phones when it was not used for some 30 years later?

 

[Brum1]

Thanks for your answer prof'

 

[NickinFrance]

The * & # keys were first used in the UK as part of the 'Star Services' provided by BT when they introduced System X exchanges between 1980 & 1990.

 

[ProfJohnL]

Hello Brum,
The move to include both * and # keys started in the 1960's when the international telecoms standards agencies decided to standardise push button keypads throughout the world. This was a natural extension and use of the way that touch tone dialling is achieved by a matrix of switches in a 3 x 4 grid

The # and * keys were utilised originally used for engineering functions (except in the UK where the exchanges could not recognise them)so the rest of the world steamed ahead of the UK in these matters.

Do you remember having to ask the international operator to set up a call abroad? - Under mounting political and commercial pressure the UK telephone system was forced to change during the 1980's to become compatible with the rest of the world and start using dual tone signalling systems.

It was only really in the 1990 when the UK's telecom providers had ousted the old pulsed dialling system and adopted the dual tone signalling method that we could start to use the # and *.

As time goes by the uses of the # and * are becoming wider. There may be international agreements on what and how they can be used for, but as they are outside of the normal decimal numbers of 0 to 9, they can (and are) used as ways for humans to confirm other numbered entries, or access methods to answer machines, and structured menus in call Centers (Big Hiss)

Last paragraph (now removed) was an incomplete early draft nad not entirly relevant. Prof John L