With car tax rises and the credit crunch affecting new and used car prices, 2009 will be an interesting time for the motor industry. But how will it affect YOU?

We list nine essential things you need to know in 2009.

1. The cost of car tax

Road tax prices are set to rise by £5 on April 1, for cars registered after March 2001. Costs will increase by up to £35 for vehicles from April 2010, or hundreds of pounds more for cars bought in 2010.

Read our 2009 road tax guide to find out how much it’ll cost to tax your car.

2. Petrol price rise?

It’s likely 2009 will be an unsteady year for oil, with price weaknesses expected to continue throughout the first half of the year.

The UK Royal Institute of International Affairs predict price rises in the second half of 2009, as the economy recovers and demand increases.

View our step-by-step fuel-saving slide show:

3. Now is a great time to buy

As the economic downturn continues, more car dealerships are offering great new and used car deals.

Motorists have seen plenty of offers in the past few months, including half-price cars, buy one get one free deals and VAT-free cars. It’s likely there’ll be lots more to come in 2009, making this a great year to buy.

4. Expect greener cars

The European Union has set an average CO2 target of 130g/km for car makers to hit by 2015. Expect plenty of new green cars and eco-friendly models to choose from.

Visit Auto Trader’s Green Motoring hub.

5. New cars of 2009

There are some massive UK car releases this year, including:

• Volkswagen Golf
• Ford KA
• Nissan GT-R
• Aston Martin One-77
• Ford Focus RS

View more images of the Ford Focus RS:

6. Take care when seeking a loan

Only take out what you can afford, and look out for high interest rates on personal loans and dealer finance options. Some dealers offer 0 per cent finance on certain models, so shop around.

Search for the best-priced loan before buying a car - you could save thousands of pounds in interest.

Visit Auto Trader Finance to compare more than 400 loans.

7. The motor shows of 2009

A range of new motor shows are just around the corner. Expect lots of new car unveilings, and complete coverage from Auto Trader.

Buyers can expect the Audi R8 V10 unveiling at Detroit on January 11, and the Porsche Panamera to make its debut at Auto Shanghai in April.

The £1m Aston Martin One-77 will likely be unveiled in Geneva on March 5 or in Frankfurt on September 17.

8. “It is going to be a rocky road”

It’s not certain whether UK car makers will receive government help in 2009.

The government’s Business Secretary, Lord Mandelson, said choosing one company to bail-out over another is a “difficult slippery slope to navigate.”

He said “it is going to be a rocky road,” regarding talks of a Jaguar Land Rover bail-out.

However the United States government offered Ford, General Motors and Chrysler £11.6bn in aid last month.

This means Ford of Europe and Vauxhall Motors UK are more likely to survive the credit crunch, as will hundreds of thousands of employees, part suppliers and franchised dealers.

9. More roads

Up to £3b worth of capital spending has been brought forward from April 2010 to April 2009. This means more housing and road projects will get underway this year.

The chancellor also promised to continue improving public services at last year’s Pre-Budget report, including public transport.

Check out the new Nissan GT-R in action:

Are you buying a car in January? Have your say on the Auto Trader Blog