With a savings account, you can add to and withdraw from it as you please. There can be some restrictions around the interest payable if you make withdrawals, however you can access the money in the account whenever it suits you. Interest rates on these accounts are generally variable and subject to change at any time.
With term deposits, an amount of your choosing (usually a minimum amount of $5,000) is locked away for a set period of time at a fixed interest rate. These rates can often be higher than a standard savings account, however the money cannot be accessed until the fixed term is over. If you choose to break the term to access the funds early, the interest payments will often be forfeited.