MPs have backed a motion allowing them to use Twitter during Commons debates.
An amendment that would have effectively banned its use - by permitting MPs to only "receive and send urgent messages" in the chamber - was defeated by 206 votes to 63.
Some MPs had argued that the widespread use of smart phones and tablet computers during proceedings would bring the Commons into "disrepute".
But others said Twitter was a valuable way to communicate with the public.
Until now there has been an informal arrangement allowing MPs to use handheld electronic devices in the Commons but not laptops.
But in January a deputy Commons Speaker told MPs they were not allowed to use Twitter inside the chamber.
On Thursday, MPs considered a motion put forward by the Commons Procedure Committee that recommended MPs be formally permitted to use electronic devices "provided that they are silent, and used in a way that does not impair decorum".
It also recommended they be allowed to refer to such devices, instead of paper notes, when making speeches, and be free to use laptops in committee meetings, including select committees.
But 11 MPs signed an amendment to that motion demanding that the use of such devices be restricted to urgent matters only.
Conservative Roger Gale said the use of Twitter would mean MPs could be subject to greater outside influence.
He said "genuine debate" was already being stifled by MPs simply reading speeches prepared for them by other people.
"If we are now to suggest that Members are going to be allowed to Twitter and receive comment in the course of these debates then it is absolutely inevitable that you will have people sitting in the public gallery sending messages saying 'ask him this, tell her that, read this'," he said.
Fellow Conservative James Gray said: "I think it brings the whole nature of debate in this place into some disrepute. I would like to see the standard of debate here maintained."
A third Conservative, Sir Alan Haselhurst, admitted his objection might make him "a leading candidate for the dinosaur of the year award", but he feared that regardless of what MPs were actually doing with the devices, they would appear to the public to be distracted.
He said he did not want to "stem the tide of modernity", but feared it could result in "a situation where it appears we are being prompted from outside" - something which would negatively impact the House's reputation.
He also said the cricket season would make it especially difficult for MPs to concentrate on proceedings in the House, adding: "How good it would be simply to see what is happening in the Test match at this particular time."
Several MPs, however, argued in passionate support of being allowed to tweet, while others suggested that the freedom to use electronic devices in general to "multi-task" while waiting to speak, or hear a particular debate, could boost the number present during debates.
Labour's Luciana Berger said only two countries in Europe currently banned MPs from tweeting during proceedings and the UK should not join them.
She said Twitter allowed MPs to "reach out to a wider audience" and to ban it would be "bemusing" to the public.
She also added that if "decorum" was a concern, some MPs had been known to have "a little snooze" in the House.
Claire Perry - in an intervention she claimed, incorrectly, was 138 characters and therefore suitable for a tweet - said "Tweeting helps MPs to stay informed, in touch and accountable to their constituents and to ban this would be an inexplicable step back in time."
Shadow deputy Commons leader Angela Smith said "it would be all too easy" to say MPs should pretend that the world had not changed, but added: "To do that would be to deny reality and to deny the dynamic relationship that now exists between Parliament and the world outside."