Best type of bird feeder for a city garden?

I now live in a city and wish to feed the birds. I already have two metal poles like shepherd's hooks which, in the past in the country, were effective against squirrels. What sort of bird feeders should I now buy that would feed small birds and bigger ones like blackbirds. Also, what feeds, please?

In the meantime the blackbirds have a wonderful time in the birdbath which I unfreeze every morning

S.

I have a pole with a seed feeder and suet holder and fat ball holder in the middle of the garden and a bird table,now they all prefer the shed roof,because they can see the enemy coming,smaller birds prefer the seed cadge near a bush or tree ,so as they can escape the sparrow hawk.We have squirrels but they are no problem here in this city.

flowering rose, thank you for all that information - I shall bear it in mind 

Do you have any sort of outside space/yard/garden or do you have a "balcony flat" or similar? If so, you'd probably be able to use the feeders you already have.  Some birds  (blackbirds for instance) are ground feeders, so prefer to take stuff from that level but will venture on to a bird table if it's big enough.The chances are you'll get pigeons too! 

I think it's a mistake to site feeders right in the open, away from places where birds can perch whilst waiting their turn, as it were, and they need to feel safe from predators as well - so if you have any large shrubs it would be a good idea to site any feeders fairly close to that sort of shelter for them.  I think you can still get a feeder which can be fixed  to a window pane, via a suction pad or two, and these are fine for the smaller agile perching/climbing birds such as blue tits etc.

Perhaps  you could take a look at another thread on this board about feeding suet etc to birds, as you'd probably find the info and suggestions useful.

Looking longer term, do you have space for a few bird-friendly bushes or fruit trees ?

If you are putting out feeders then caging and height (eg screw some onto the wall of the house - away from cats and squirrels) is the way to go.

I recently bought a square clear plastic feeding box which is fixed to my window with 3 suction pads. I found it in a garden centre and cost £12.99.

It is quite near the feeding station and it took about 4 days before the birds plucked up the courage to try it out. Now it is very busy every day. Mainly a variety of tits and the robins. It is too small for bigger birds. It is lovely to be so near to the birds which do not seem bothered by me sitting indoors watching them within inches.