IBM is celebrating 50 years since the launch of its System/360, a line of mainframe systems that set new expectations for what a computer should be and defined the public perception of the mainframe to this day.

While the System/360 was not strictly the first mainframe, it marked a major step forward in the development of the computer, introducing many concepts that we take for granted today. The latest generation of IBM's System z servers can trace its lineage directly back to the System/360 family launched on 7 April 1964, and it even maintains a measure of software compatibility with the original hardware.

But in this era of cloud computing and mobile devices, many readers must be questioning the relevance of the mainframe in the modern world, especially as there is effectively only one mainframe vendor left in business IBM.

However, many critical services are still handled by mainframes, including the majority of credit card transactions and many airline reservation and check-in systems, according to IBM.

The truth is that the mainframe still does the job it was built for, and many of the rival technologies that have come along since still can't match the reliability and high level of availability offered for mission-critical applications, according to Roy Illsley, principal analyst at Ovum.

"It's survived very, very well, it does what it says on the tin, customers trust it, new engineers are being trained to use it through graduate programmes from the likes of CA and BMC, and they are modernising it, so it's going to be part of the IT landscape for the foreseeable future," he told V3.

In fact, the introduction of Linux on IBM's mainframes a few years back gave a new lease of life to the systems, Illsley observed. With pricing for some new zEnterprise systems starting in the range of 40,000, IBM's mainframes are beginning to look like an attractive alternative to high-end Unix systems.

"Bottom-end mainframes are really challenging what the Unix boxes can do, and the x86 systems are now pushing up into that space as well, so it's really Unix that is feeling the squeeze," he said.