Socializing Parrots

How does one socialize a young parrot?
Is it done in a similar way as socializing a puppy?
Is there a point in a parrot's life where socialization is too late/does no good?
Is socialization different for each species?

I would find that socializing starts off at home with each member of the family. Getting them used to being on someone elses arm or hand then slowly moving the process to where they can be passed on to different people - maybe outside people like friends or neighbors when they come over. It's also good to get them used to new environments, playing with them in one room then another and then another. I don't have a lot of room so I take my birds on walks , I have them in their carriers and walk around the block a few times to let them get used to being outside. Other than that, I have them outside on the perch where it's not too sunny. I also do my best to try take them with me (mostly Gizmo) to malls if it's early in the day to let him get used to different people. I usually let the people who want to interact with him touch him through the bars so I don't get in trouble.

Socialization is pretty different, dogs will pretty much go to you for treats then have an instant relationship where birds will pick who they want to go to. (That's why taming/bonding with a parrot is more difficult then bonding with a dog).

Birds of any age could be socialized through a lot of patience and guidance (much like training). It shouldn't be impossible, more like frustrating, but it should be doable.

Socialization shouldn't matter on which species more towards the individual, IMO. You could have a pair of Amazons where one loves to go outside and meet new people while the other is a bit more fearful of going outside. You would really just have to work out around the bird and their limits then progress upwards with them.

(Sorry, my thoughts are all jumbled--I got up maybe 10 minutes ago and i need my thoughts to get together, let me know if anything needs clarification).

Thank you! This is extremely helpful.
I have noticed this with my 'Tiel. She was very wary of people, I couldn't get her to step up for anything. About five months later (now) she steps up almost every time, gives kisses, flies to my hand/forearm, tries to eat off of our plates, etc.
It has definitely been rewarding.