The money you receive for doing your job is your salary. A salary is usually the same amount every month; it doesn't change based on the exact number of hours you work.
A wage is when you receive money based on the number of hours you work: If you work 1 hour, you get a certain amount; if you work 4 hours, you get 4 times that amount. Also, the minimum amount of money (either hourly or monthly) that employers MUST pay their employees by law is called the minimum wage.
Your income refers to ALL the money you receive. It includes your salary or wage, but may also include money received from investments. If you have a house or apartment which you rent to other people to receive money, that money is also part of your income (but it is not a salary or wage, because it doesn't come from a job).
No British Christmas is complete without a Christmas pudding and despite this wildly popular dessert (outside the UK, too) not being as delicious as some might imagine, it has become an ultimate Christmas symbol, at least throughout the UK.