Synthetic oil typically lasts for around 6-12 months depending on how much you drive. After 7,000-10,000 miles of coverage you'll want to replace the oil with fresh synthetic.
Synthetic oils are a type of oil that is chemically manufactured. They are made by blending various hydrocarbons to form a homogeneous fluid.
Synthetic oils were first developed in the 1920s and 1930s. The first synthetic oil was created from coal tar, but it was difficult to formulate and use in engines.
Synthetic oil is more expensive than traditional oil, but it's better viscous and can flow better at low temperatures.
One person's experience of oil changes will vary depending on the nature of their car. For instance, a person would change their oil more often with a car that is prone to getting dirty/gaining mileage faster than others.
Manufacturers recommend changing your engine oil at different intervals, depending on how you drive.
Synthetic oil is a long-lasting and sustainable option that can cover up to 15,000 miles before it needs to be changed.