Andy Jassy is not a household name.

He is, though, about to take on one of the biggest jobs in global business - replacing Jeff Bezos as chief executive of Amazon.

Accompanying the appointment of a new football manager comes endless speculation. What will the style of play be? Are they the right fit at the club? Can they manage the big stars?

Business is no different.

Yet with Amazon's new chief executive, we kind of know what to expect.

Amazon's business is so big it essentially acts as an umbrella organisation for many different companies.

Mr Jassy has been at the company for 23 years, conducted plenty of interviews, and has been pretty open about what makes him tick.

He also runs its most lucrative business - Amazon Web Services (AWS).

Amazon's quarterly results, announced on Tuesday, confirm that AWS is the driving force behind its profits - accounting for about half of the company's operating income.

It saw the potential for the outsourcing of computing and storage, that companies use to run things like websites, before its rivals.

Google and Microsoft got into the game later - and now offer similar services. However, there's a clear market leader in the field, and that's Amazon.

According to one estimate, AWS accounts for about a third of worldwide cloud infrastructure spend.

It's a long way away from where Amazon started - as an online shop selling books.

Mr Jassy, who founded AWS in 2003, nurtured this side-bet of Amazon's into a money-spinner - and became the obvious successor to Mr Bezos.

And the way Mr Jassy has relentlessly developed AWS is strikingly similar to the way Mr Bezos went about building Amazon, and he is most certainly moulded in his predecessor's image.

AWS has become so successful it's even become a focus of anti-trust campaigners - and the Federal Trade Commission. So should it be hived off from Amazon entirely?

Investors want Amazon to have many more offshoots like AWS - hugely profitable firms all under the company's banner.

That's what Mr Jassy has delivered before, and that's what they hope he can do again.

Amazon has a burgeoning advertising business. It has acquired companies like Whole Foods and Ring home security systems, and is venturing into pharmacy. And don't forget Amazon Prime. All of these businesses have plenty of room to grow.

You might expect shares in Amazon to take a dive on the news that Mr Bezos had stepped back. But the market seemed pretty relaxed about the move. They know Mr Jassy, and see him as an able replacement.

It's not uncommon for a hyper-rich founder to do this - there are precedents. Think of Sergey Brin and Larry Page at Google or Bill Gates at Microsoft. Those two companies have done fantastically well under Sundar Pichai and Satya Nadella respectively.

And Mr Bezos is not leaving, remember. He'll be less involved in running the everyday aspects of the company, but Amazon is still his baby, he'll still be the most influential person in whichever room he finds himself at the company.

Mr Bezos's move then is capturing headlines. However, Amazon has become a very big, very successful company - and that's likely to continue under Mr Jassy.