Microsoft is (once again) the world's most valuable tech company after its market value climbed past the $US1,000,000,000,000 mark — for about half an hour.

Key points: Apple and Amazon were the first companies to be valued at $US1 trillion.

Apple and Amazon were the first companies to be valued at $US1 trillion. Their values have since fallen as global markets entered into a correction in late-2019

Their values have since fallen as global markets entered into a correction in late-2019 Microsoft's surge in market value was driven by its cloud computing business

Apple and Amazon are the only companies to have previously cracked the trillion-dollar milestone, before their shares plummeted, along with global markets in late-2018.

The excitement that drove up Microsoft's share price was generated by its quarterly earnings, released on Wednesday evening (local time), which smashed market expectations.

In extended trading, Microsoft was able to briefly join the exclusive 13-digit club when its share price jumped as high as $US130.87.

However, its after-hours share price then drifted back to $US129.35, which takes its market value to $US992 billion.

Profits up in the cloud

The technology giant's revenue jumped 14 per cent to $US30.6 billion.

"Demand for our cloud offerings drove commercial cloud revenue to $US9.6 billion this quarter, up 41 per cent year-over-year," Microsoft's chief financial officer Amy Hood said, in a statement explaining the results.

Microsoft's "commercial cloud" revenue includes business use of Azure, Office 365 and professional networking website LinkedIn.

Azure, in particular, experienced rapid revenue growth of 73 per cent.

LinkedIn — which Microsoft acquired for $US26 billion three years ago — saw its revenue lift 27 per cent during the quarter, and is growing much faster than Microsoft as a whole.

The results show that Microsoft has benefited from adapting its business model — a growing proportion of its software sales come from recurring subscriptions, as opposed to one-time purchases.

"We are accelerating our innovation across the cloud and edge so our customers can build the digital capability increasingly required to compete and grow," said Microsoft's chief executive Satya Nadella.

The trillion-dollar club

Apple was the first publicly-listed company to cross the $US1 trillion mark last August — its share price surging more than 50,000 per cent since 1980, when it debuted on Wall Street.

This was followed (briefly) by Amazon in early-September, which only took 21 years to reach the milestone.

But the euphoria among investors was short-lived as the tech giants — along with global stock markets — saw their values plunge into correction (then bear market) territory by the end of the year.

The sell-off was caused by rising US-China trade tensions, and investors panicking that the Federal Reserve would aggressively hike interest rates due to its confidence in the US economy, raising the cost of borrowing money.

However, the geopolitical and economic environment has undergone a complete reversal since then.

Washington and Beijing are reportedly close to signing a deal to end their protracted trade war, in which both sides imposed tariffs on hundreds of billions of dollars of each other's imports.

In a stunning reversal, the Fed said it would abandon plans to lift interest rates in 2019 due to concerns about slowing growth in the global economy.

Many analysts and traders are even expecting the US central bank to go further by cutting rates this year.

This has caused share markets to rebound and, earlier this week, Wall Street went back to hitting record-highs and tech stocks are back in fashion.

Apple and Amazon are now worth $US981b and $US945b respectively, according to their after-hours share prices.

Amazon is set to announce its quarterly earnings after the closing bell on Friday, while Apple is scheduled to report on April 30.

If both companies unveil stellar results in the coming days, they will be within striking distance of rejoining the trillion dollar club — and possibly staying there for longer than a few weeks (or minutes).