Inflation is a general rise in prices across the economy. Inflation has an effect on your savings because the money you save will buy less each year and there is a risk that your savings will not keep pace with inflation.
To protect your savings against this, you should look for an after-tax interest rate (net rate) that is more than the rate of inflation.
Or if you want to put your money away for a longer period and are prepared to take the risk that your money could fall in value (as well as rise), you could put some into an investment product linked to the stock market.