This is the student version - to which the readers are free to add on and comment upon. A Professor/Teacher at any given instance of time may belong to one or more of the categories.
# The OK Professor
This is the really annoying kind. Talking to them is a real pain in the neck. Their lectures are peppered with OKs, Does This Makes Sense and aahh.. aahh..
They are really nervous while teaching. Or probably, they developed this bad habit in spite of all the training.
In one class that I still remember, the professor had uttered 180 OKs in a span of 30 minutes - that averages to 6 OKs per minute! Or an OK every 10 seconds! Does that make sense? OK?
# The Somnolent Professor
Though the professor is a master in his subject and his presentation is immaculate, there is something in his lecture that puts everyone to sleep.
The professor may not realize it but half the class would be sleeping. It maybe because of his dull voice (rather monotonic?), probably his haphazard manner of going about things or it maybe just nothing at all. But he justs puts everyone to sleep.
# The Peace Maaru Professor
Really doesn't believe in working very hard. Will teach as much as he is paid for. Nothing more.
Comes to the class 10 minutes late and leaves the class 10 minutes early. Solves a question on the board in the whole class and doesn't bother the students much. His policy is - "Live and let Live".
# The Dynamic Professor
This is the professor who feels that the students should get the best out of his class. He gives them a lot of assignments and takes surprise tests.
He is young, energetic and full of passion for his subject. He thinks - "I should try to become the Ideal (Utopian?) professor."
# The Motivators
These are generally the old guys. Already in the teaching profession for 20 to 30 years, they know that whatever they teach is not going to make much of a difference. If however they can motivate some of the students to do something in life, they would have accomplished something.
Their lectures are filled with quotes from the Gita and the Bible. They borrow extensively from Shiv Khera and think that their plagiarism would go unnoticed. One can stand them for a day or two but the rest of their lectures are just "Rewinding the Tape".
# The Pundits
The really knowledgable ones. They have worked in the industry for some time and their breadth of knowledge puts you to awe.
But their lectures are hardly organised. They would start of with programming in C and end up with the reactions that take place in a rocket launcher.
Their lectures can be really hilarious and fun. But it won't do you any good for your exams.
# The Sadists
They may not be sadists at heart. But some of their activities really annoy the students.
If they are invigilators in the exam hall, they might as well throw out half the candidates out of the hall for plagiarism/not bringing admit card/ringing of the mobile phone.
When they evaluate the papers, one really wonders if he had been having breakfast while evaluating the paper. And worse of all, when the answer scripts are shown, the professor is out of town.
They may be excellent teachers. But rarely student friendly.
# The Liberals
They are the modern professors. They believe in modern methods of teaching. They ask students of the opposite gender to sit together in class and they come in casuals instead of formal wear to class.
Their evaluation is liberal and they are a real hit with the students.
I will stop here. I think this is the basic classification. Did I miss any? Have any to add on to this? Do let me know!
Posts
If you observe - ONO is a natural ambigram. That made my task easier! :D 
There you are. This is what I was talking of. This is a subtle variation of the chest thump we do with our fists when we are proud of ourselves. The Bryan Brothers are proud of each other.
Insults or complaints or bricks
Stilled the frogs determination
To display his heart's elation.
But one night a nightingale
In the moonlight cold and pale
Perched upon the sumac tree
Casting forth her melody
Dumbstruck sat the gaping frog
And the whole admiring bog
Stared towards the sumac, rapt,
And, when she had ended, clapped.
Ducks had swum and herons waded
To her as she serenaded
And a solitary loon
Wept, beneath the summer moon.
Toads and teals and tiddlers, captured
By her voice, cheered on, enraptured:
“Bravo!” “Too divine!” “Encore!”
So the nightingale once more,
Quite unused to such applause,
Sang till dawn without a pause.
Next night when the Nightingale
Shook her head and twitched her tail,
Closed an eye and fluffed a wing
And had cleared her throat to sing
She was startled by a croak.
“Sorry – was that you who spoke?”
She enquired when the frog
Hopped towards her from the bog.
“Yes,” the frog replied. “You see,
I'm the frog who owns this tree
In this bog I've long been known
For my splendid baritone
And, of course, I wield my pen
For Bog Trumpet now and then”
“Did you… did you like my song?”
“Not too bad – but far too long.
The technique was fine of course,
But it lacked a certain force”.
“Oh!” the nightingale confessed.
Greatly flattered and impressed
That a critic of such note
Had discussed her art and throat:
“I don't think the song's divine.
But – oh, well – at least it's mine”.
“That's not much to boast about”.
Said the heartless frog. “Without
Proper training such as I-
And few others can supply.
You'll remain a mere beginner.
But with me you'll be a winner”
“Dearest frog”, the nightingale
Breathed: “This is a fairy tale –
And you are Mozart in disguise
Come to earth before my eyes”.
“Well I charge a modest fee.”
“Oh!” “But it won't hurt, you'll see”
Now the nightingale inspired,
Flushed with confidence, and fired
With both art and adoration,
Sang – and was a huge sensation.
Animals for miles around
Flocked towards the magic sound,
And the frog with great precision
Counted heads and charged admission.
Though next morning it was raining,
He began her vocal training.
“But I can't sing in this weather”
“Come my dear – we'll sing together.
Just put on your scarf and sash,
Koo-oh-ah! ko-ash! ko-ash!”
So the frog and nightingale
Journeyed up and down the scale
For six hours, till she was shivering
and her voice was hoarse and quivering.
Though subdued and sleep deprived,
In the night her throat revived,
And the sumac tree was bowed,
With a breathless, titled crowd:
Owl of Sandwich, Duck of Kent,
Mallard and Milady Trent,
Martin Cardinal Mephisto,
And the Coot of Monte Cristo,
Ladies with tiaras glittering
In the interval sat twittering –
And the frog observed them glitter
With a joy both sweet and bitter.
Every day the frog who'd sold her
Songs for silver tried to scold her:
“You must practice even longer
Till your voice, like mine grows stronger.
In the second song last night
You got nervous in mid-flight.
And, my dear, lay on more trills:
Audiences enjoy such frills.
You must make your public happier:
Give them something sharper snappier.
We must aim for better billings.
You still owe me sixty shillings.”
Day by day the nightingale
Grew more sorrowful and pale.
Night on night her tired song
Zipped and trilled and bounced along,
Till the birds and beasts grew tired
At a voice so uninspired
And the ticket office gross
Crashed, and she grew more morose -
For her ears were now addicted
To applause quite unrestricted,
And to sing into the night
All alone gave no delight.
Now the frog puffed up with rage.
“Brainless bird – you're on the stage –
Use your wits and follow fashion.
Puff your lungs out with your passion.”
Trembling, terrified to fail,
Blind with tears, the nightingale
Heard him out in silence, tried,
Puffed up, burst a vein, and died.
Said the frog: “I tried to teach her,
But she was a stupid creature –
Far too nervous, far too tense.
Far too prone to influence.
Well, poor bird – she should have known
That your song must be your own.
That's why I sing with panache:
“Koo-oh-ah! ko-ash! ko-ash!”
And the foghorn of the frog
Blared unrivalled through the bog.