W.Salam

I will try best of my knowledge to answer these questions

1-A, Had
*It is the punishment prescribed as a right of Allah, both quantitatively and qualitatively.
*Hudood are mentioned clearly in Quran and Hadees, on which act it would be implemented and how to be executed.
*No one at any time cant change it(Tradition about Hazrat Umar R.A that he temporarily lifted the punishment of amputation for a theft), it was specified with special event, reason was famine, secondly he imposed the condition that only that person would be released who stole for survival not for hoarding.
*conditions of implementation could not be changed in any circumstances e.g: Who is liable for stoning due to adultery, and the evidences which are mandatory against the allegations would remain the same in every state and case. Ijtehad could be done as in the case of Umar R.A
**Acts resulting in hadood are
1-Adultery (Different hud for married and single), (24:2)
2-False allegation of Adultery
3-Drinking (Some used to include it in Tazeerat as quantitative hud is not mentioned in quran and I think neither in saheeh hadith)
4-theft (5:38)
5-bloodshed (Qisas and Blood money)(2:178)
6-Apostasy &
7-Rebellion

1-B,Taazir
*A corrective measures for which no huds have been laid down in the shariah
*3 Kinds
1-Punishment for crimes (forbidden by shariah but hud is not entitled
2-punishments for offences against public interest
3-for misdemeanor
*e.g: on adultery all schools of thought are unanimous on stoning or lashes but for a single(un married) with lashes is expelling from country is also a hud or tazeer? Mostly jurists says that it is tazeer depending on the verdict of court
*Tazeer could be changed by time, Drinking is an example of it as in some Traditions it is found that drunk were lashed but the number of lashes were different in different cases, this is the reason some jurists entitled drinking to tazeer

2-Sources of Islam
there are four sources of Islam
1- Quran
it is the first source of Islam, 5:3, 2:2, 2:185, the only heavenly book which is in its original form, From Allah to Prophet through jibraeel, no one can doubt the three, it is completed in the life of prophet and written and memorized by Companions, umme warqa among the female companions were hafiza, words and meanings both from Allah

2-Hadith
Prophets words are same in value as of Quran, it is the exegesis of Quran, difference is that in Traditions worthiness of hadith could be criticized as different categories of Hadith are developed and different Ulum were developed like Usul e Hadith for check and balance of Ahadith, 53:3&4 Nahal:44 Nisa:80 Hashar:7,

3-Ijma Consensus of opinions
literally it means acceptance of certain idea unanimously, Yunas:71, Defination is Unanimous decision by jurists of same era after the demise of Prophet,
Conditions
1- the consensus must be among the jurists
2- among all the jurists of the time
3- All should be muslim
4- After the consensus no one could offend
5- the verdict must be about the islamic issue for instance consensus of Mujtahids for medicine would not be entitled as Ijmaa
6- Without Shari evidence ijma could not take place
It is of two types
1- sareehi and Sakooti

4-Qiyas
literally its mean to compare one thing with an other or weigh one thing with another. Prohibition of Drinking is clearly mentioned in Quran and Sunnah but of Heroine or Opium? So we have to qiyas it on Drinking.
Certain Features and Conditions of Qayas
parts of Qayas (Qayas is a work, verb)
Maqees alaih, original matter with which the object (opium) have to be compared (e.g: Drinking in above example)
Maqees (Opium)
illat (e.g: Intoxication which is a similarity between drinking and opium)
hukam (Haram in above example),

In fact basic original sources are two Quran and Hadith, all others are the subordinates or branches of Base, for Instance some of the jurists prefer istehsan instead of qiyas etc,

but as per syllabus or norm 4 are usually described

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Janoon say or Ishq say milti hay AAZADI