The public finances: Reduce the deficit but 'fairly' and borrow to invest
Growth not austerity is the thrust of Corbyn's economic plan. A National Investment Bank would be set up to invest in green energy, digital infrastructure and a massive housebuilding programme.
The aim would still be to reduce the deficit, but 'fairly'.
Corbyn says that if the deficit has been closed by 2020 - as the Tories want it to be - and the economy is growing, then he will only borrow to invest in future prosperity.
His biggest headline-grabber has been the suggestion of People's QE to fund his infrastructure plans, which we explain below.
But this is only one option put forward to pay for his goals of building up the economy, and rebalancing it away from finance towards what he sees as the high-growth, sustainable sectors of the future.
The other option the veteran left-winger suggests is to cut back on some of the £93billion a year he claims is spent on tax relief and subsidies to business - money which he reckons would be better used for direct public investment.
Meanwhile, Corbyn says he would end the public sector pay freeze, and he is a staunch opponent of welfare cuts. He argues that austerity is about political choices not economic necessities - and that there is money available.
He points as proof to two measures in Chancellor George Osborne's Budget in July costing £2.5billion apiece - another corporation tax cut, and an inheritance tax break for the richest 4 per cent.
Corbyn says: 'We all want the deficit closed on the current budget, but there was no need to try to do it within an artificial five years or even the extra five years George Osborne mapped out.
'If the deficit has been closed by 2020 and the economy is growing, then Labour should not run a current budget deficit – but we should borrow to invest in our future prosperity.'
Would it work?
Economists are a fractious lot but Corbyn's opposition to austerity has attracted support from more than 40 of them in one of those open letters to a newspaper that never go out of fashion.
It is worth noting, however, that many of these economists were already vocal critics of austerity.
They say Corbyn's stance is mainstream economics, and it is the Government's plan to balance the budget primarily through spending cuts which is extreme.
A Corbyn-led government would most probably fund any public investment programme through borrowing, especially if interest rates were still at their current low levels.
Borrowing to invest is a far from remarkable thing to do.
Although 'real world' analogies are dangerous - government finances work differently from household budgets or company balance sheets - it's fair to point out that borrowing to invest is a pretty commonplace activity.
Ordinary people get mortgages for the entirely reasonable goal of owning their own homes, and businesses take out loans in order to expand.
The key when governments borrow to invest is putting money in projects that will either generate growth through a multiplier effect, or provide other worthwhile social benefits such as ending up with some new schools and hospitals.
But to be successful in this, Corbyn would have to pick the right public ventures to invest in and ensure they were managed competently.
The other option he puts forward to fund his National Investment Bank and promote economic growth is diverting money from corporate tax relief and subsidies - although he says only some of it, not the entire £93billion.
The trouble is much of this money is supposed to encourage and support business investment and if that dried up it would be counterproductive during a growth drive. These are tax breaks designed to boost the economy.
A Corbyn government would need to distinguish between the helpful types of corporate tax relief which should stay, and the handouts that could be safely scrapped.
The People's QE: The most controversial policy
One of Corbyn's most eye-catching proposals has been 'quantitative easing for people instead of banks' - printing money to invest in socially useful public projects.
The QE that Britain has already seen since the financial crisis involved the Bank of England creating money to buy government bonds from financial institutions - the idea being that these funds would trickle down into the economy. There is much debate as to the exact benefits it delivered.
Corbyn's version of money-printing would be different and aimed at directly boosting infrastructure.
His economic adviser Richard Murphy wrote in a blog post: 'I have been, and Jeremy Corbyn has also been, very keen to make clear that the Bank of England will not be investing in roads, or houses, or green energy.
'It would in fact be buying bonds from a National Investment Bank which would, under government direction and subject to government guarantees, engage in such investment issues. All that the Bank of England would do would buy some new forms of bond: it would not manage a single project or decide upon any investments.'
Murphy says that People's QE would not only be used in a crisis but it would not be needed if the economy was running well. He claims that the economy is not running well at the moment.
Corbyn says: 'One option would be for the Bank of England to be given a new mandate to upgrade our economy to invest in new, large-scale housing, energy, transport and digital projects: quantitative easing for people instead of banks.'
Would it work?
Government investment in public infrastructure to crank up economic growth in hard times is certainly nothing new.
It's based on the ideas of economist John Maynard Keynes and was most famously put into practice by US president Franklin D. Roosevelt in his New Deal programme to combat the Great Depression in the 1930s.
Whether it's a good idea to fund this kind of initiative using quantitative easing - or whether Keynes or Roosevelt would have approved - is another matter.
Printing money when the economy is chugging along satisfactorily would risk inflation.
As it is, QE as employed so far hasn't caused inflation the way many warned, but it has skewed stock, bond, currency and commodity markets in ways we haven't yet fully understood and the fallout is still unknown.
In reality, it's unlikely the Bank of England - which is officially independent - would agree to print money to pay for such a programme unless we were in another dire economic crisis.
But if we did, the Bank might agree to try using QE cash for worthy public works rather than shovelling it into banking sector again.
This is Money Editor Simon Lambert suggested back in 2012 that if we were going to print more money, we should do something more useful than just pumping it into the financial system. At that point the economy was judged to be in crisis, however, and a fresh bout of QE was being called for.
'There’s certainly some dodgy railways, substandard or too small schools, closing hospitals, energy underinvestment, £9,000-a-year university bills, apprentice training schemes and pothole-ridden roads that would benefit from a bit of massaging with that kind of money,' he wrote at the time.
If QE was used to fund public projects, the challenge of how to unwind it again would have to be faced, just as with the type already employed by the Bank.
One economist, Tony Yates, formerly of the Bank of England, is heavily critical of the idea. He wrote: 'Corbyn’s QE is the first step along the road to undermining the social usefulness of money, and would ultimately impoverish us.'
Renationalisation: Railways run by the people, for the people
Bringing the railways and the energy sector back into public ownership is a major plank of Corbyn's programme.
His campaign agent John McDonnell has also reportedly threatened to buy back public assets sold by Osborne - presumably including the taxpayers' stake in Royal Bank of Scotland if it had been sold off - either with no compensation, or with deductions for any undervaluation at the time of the sale.
McDonnell writes on his blog: 'Public ownership does have an important role to play, but this will be through smart forms of 21st-century common ownership and control. For example, rail will be renationalised, but with a form of joint management involving workers and passenger representatives.
'Energy would be socialised from below by the massive expansion of renewable energy production and supply by local communities, local authorities and co-ops on the successful German model, removing the monopoly of the big six energy companies.'
Corbyn says: 'We need to rebuild an integrated publicly owned railway network that is run by the people for the people.
'The rail franchising process is incredibly expensive and wasteful, both to bidding companies (which pass on costs through higher fares) and to the government to administer the process.'
Would it work?
Many people are unhappy with how the rail companies and energy giants are run at present so this would be popular.
The problem is how you fund renationalisation. Even if you waited until the current franchises ended to avoid buying companies out, it would still cost the Government money to resume ownership of the railways.
That said, Britain's railways take a lot of money in subsidies to provide an expensive service many people are not happy with, while delivering profits for shareholders.
As for the outlay needed to renationalise the energy suppliers, estimates vary but figures ranging from £124billion to £185billion have been chucked about since Corbyn made his intentions known.
Public support for his policy would no doubt dwindle if taxpayers were faced with that kind of bill.
The energy market has also become more competitive in recent years. It is dominated by the Big Six suppliers, but smaller players such as Ovo and First Utility are eating into the customer base of the big guns.
Meanwhile, it's unlikely that a Corbyn government would actually seize public assets sold off by Osborne without paying compensation.
Emerging market countries sometimes indulge in forced nationalisations, but they suffer more than they gain as investors shun and punish them for years to come.
Developed economies like the UK just don't do that kind of thing. If Corbyn tried, he'd probably also face legal action from investors.
Tax: Tackle the dodgers and put the squeeze on big companies
The government is missing out on nearly £120billion in tax revenues a year, according to research cited by Corbyn.
This sum breaks down as £20billion in tax debt uncollected by HMRC, £20billion in tax avoidance and £80billion in tax evasion.
Corbyn wants to claw it back via measures including the introduction of an anti-avoidance rule into UK tax law, country-by-country reporting for multinational corporations, reform of small business taxation to discourage avoidance and tackle evasion, regulation of companies to ensure they file accounts and tax returns and pay what they owe, and a reversal of staff cuts at HMRC and Companies House.
He would also restore maintenance grants and scrap university fees for students, and is asking for feedback on two options to foot the bill.
These are either using part of a projected £15billion increase in income tax receipts between 2019/20 and 2020/21, or using a mixture of a hike in corporation tax from 20 per cent to 20.5 per cent plus the introduction of a 7 per cent rate of National Insurance for higher earners - expected to be those earning more than £50,000.
Meanwhile, Corbyn backs the Robin Hood Tax campaign, which is calling for a small tax levy on transactions in financial assets like stocks and derivatives.
Corbyn says: 'The biggest issue facing British politics right now is not whether the top rate of tax should be 45 per cent or 50 per cent, or whether corporation tax should be 18 per cent or 20 per cent.
'The big question is how to get some of the wealthiest individuals and biggest corporations to pay anything like their fair share.'
He adds: 'Paying tax is not a burden. It is the subscription we pay to live in a civilised society.'
Would it work?
Perhaps the Government is missing out £120billion in revenues a year, but if it was easy to grab that amount of cash off the tax shirkers then Osborne would surely have tried it by now.
Hiring more HMRC staff might help but that is by no means certain. All politicians promise a tax crackdown before they arrive in office but tend to find this harder than they imagined in practice.
Corbyn also seems to be lumping in tax avoidance, which is legal, with tax evasion, which is illegal.
Unless he changed the law, it would be next to impossible to get hold of money lost through the former activity.
Business and work: Up the workers and down with Murdoch
An end to zero hours contracts, strong collective bargaining in workplaces, and measures to help small businesses such as a rate freeze and rent controls, are among Corbyn's plans for the corporate sector.
In an interview with the FT, he also strongly hinted he would break up Rupert Murdoch's media empire.
Corbyn says: 'The current government seems to think being "pro-business" means giving a green light to corporate tax avoiders and private monopolies. We will stand up for small businesses, independent entrepreneurs, and the growing number of enterprises that want to co-operate and innovate for the public good.
'We will also address two key issues holding back British business: lack of skills and of investment.'
Would it work?
A Corbyn government would undoubtedly pursue more worker-friendly policies than the country has been used to since the days when union barons wielded great power back in the 1970s.
Those who think bosses are now the ones who are too over-mighty - not to mention overpaid - would certainly enjoy seeing them brought down a peg or two.
But would Corbyn really win a full-on knock-down battle with Murdoch? Many would bet on Murdoch emerging with his media interests intact.
Housing: Mass building drive and more help for tenants
The housing crisis should be met with a drive to build at least 240,000 new homes a year, according to Corbyn.
He wants to clamp down on 'off plan' sales to overseas buyers who treat homes as speculative assets, and levy a tax on owners sitting on land which has planning permission but is not being developed.
Corbyn is critical of 'right to buy' schemes for council and housing association tenants, but he suggests investigating some form of right to buy shared equity scheme for private tenants renting from large-scale landlords.
Other measures to support tenants include rent controls linked to average earnings and their rate of increase rather than the market rate for housing, and registering and licensing private landlords.
Corybyn also wants the bedroom tax and the housing benefit cap scrapped.
Corbyn says: 'The free market free-for-all in housing has failed. Only the government is able to play the strategic, co-ordinating role to tackle the housing crisis.'
Would it work?
Osborne has meddled so much in the housing sector since the financial crash that it can't really be called a free market.
So far all Osborne's measures - such as Help to Buy - have tended to pump up buyer demand and therefore prices, when the consensus is that it's housing supply that needs tackling first.
Corbyn wants to build masses of new homes, including a lot of new council properties, but of course this would cost a lot. How much he could actually spend would depend on getting his National Investment Bank off the ground and making a success of his wider economic policy of focusing on growth rather than austerity.
His proposals to ease the plight of tenants are likely to be popular with young people stuck in rented accommodation because they can't afford to get on the housing ladder.
There seems no reason why cleaning up some of the worst excesses of the private rental market would do any harm. Other countries, such as Germany, manage to ensure tenants are treated fairly without destroying their housing market.
It is worth noting, however, that there are many people who believe that the root cause of house prices spiralling higher than any increase in wages is cheap credit - with the lack of new homes a contributing factor.
