You'll be automatically enrolled if you're not already in a workplace pension scheme, if you're aged 22 or over and you earn at least £675 per month (which equates to £8,105 per year).
The Government has set a minimum percentage that has to be contributed in total. This will start at 2 per cent and increase to 8 per cent over the next few years. This total is made up of your contribution, your employer's contribution and the Government's tax relief, all added together.
Eventually, by the year 2018, you'll be putting in 4 per cent of your gross salary, your company will add another 3 per cent (minimum) on too and you'll get tax relief from the Government.
These percentages do not apply to all your earnings, but just to what you earn between £5,564 and £42,475 per year.
If you opt out of this workplace pension scheme, then you could end up with only the basic state pension to support you. It's a good foundation, but you may well want more.