A technology entrepreneur has pledged to give £1m to The National Museum of Computing (TNMOC) at Bletchley Park.
The offer is the largest ever single donation given to the museum that curates, repairs and stores ageing computers.
The museum said the cash would be used to refurbish the museum to help it handle more visitors and display more of its historic computers.
The cash has been promised by British IT veteran Matt Crotty.
To get the cash TNMOC must also do its own fund-raising as the money has been pledged on a "matching funding" basis. This means that Mr Crotty will match every future donation given until a total of £1m has been reached. TNMOC is now starting a funding drive to secure cash to match the pledge.
Thank you Matt