Basically it is a doctrine which means "Law made by judges" & it is one of the major sources of Law which is contributory in nature in the form of making the new Laws.
It is a decision taken by a Court which will be a benchmark and used for future reference in decision making by the subordinate Courts while the legal facts and issues are exactly the same.

In the other word it is something which past decisions help to make future decisions.

Judgments passed by the higher judiciary are applicable to the same on the lower judiciary. Which means the judgment passed by the High Court follows by the Lower Courts, the Supreme Court judgment follows by the High Courts, Lower Courts & the Supreme Court itself means higher division bench to lower division bench.

All the subordinate Courts are bound to follow where the legal issues, facts and  circumstances are sufficiently similar.

Meaning & Definition:
Judicial Precedents means in general terms a behavior which is previously adopted becomes an example or rule for subsequent cases.

For example in the case of Kesavananda Bharati the basic structure doctrine of the Indian Constitution was propounded which is applicable as a precedent in the case of Indira Gandhi Vs. Raj Narayan,  Minerva Mills and other cases where the facts of the case and the circumstances are subsequently similar.

It may be defined as a decision by a competent Court of justice upon a disputed point of Law becoming not merely a guide but an authority to be followed by all the same system until it has been overruled by a superior Court of justice or by statute.

Enactment & Provisions:

• Judicial Precedents were enacted from 1950 after the making of the Constitution
• Article 141 of the Indian Constitution talks about decisions of the Supreme Court.
• Article 225 of the Indian Constitution talks about decisions of High Courts making them obligatory for their subordinate Courts.

Doctrine of Stare Decisis:

• The doctrine of "Stare Decisis" which means "to stand by what has been decided
• This means that judges follow the legal principles already established in earlier cases.
• This ensures consistency in the Law and predictability.
• It's presumptions are based on the hierarchy of the Courts and the Courts are bound to follow the Court decisions by their chronological order. In case of an equivalent court they have persuasive value which means they respect the decision but are not bound to follow it.

Fundamental Principles:

• It is 'like cases should be treated alike'.
• A rule followed or a principle applied by a competent authority under similar facts and circumstances.
• When the judges interpret the Law by establishing new rules and principles which are binding on lower Courts known as 'Judicial Precedents'.

Kinds of Precedents:

The word precedent means some pattern.

There are four different kinds of precedent such as follows:

• Absolute Authoritative Precedents:
  Which are binding on all the Courts. It is binding  upon the judges who interpret the Law; they can be regarded as a legal source of Law. It is a rule of Law. For example a decision of the Supreme Court or the decision of any superior Court's bound to follow by the subordinate Courts.
   
• Persuasive Precedents:
  The precedents which the Courts are not bound to follow, though they may be taken into consideration while giving character and only a historical source of Law. It means the decision of the High Court is an authoritative precedent within the jurisdiction of that High Court but outside the decision of that High Court is not authoritative but only guiding or persuasive text books and commentaries. For example, Delhi High Court decisions are not bound to follow the Mumbai High Court; they may or may not but can take the reference always.
   
• Original Precedents:
  According to Salmond, which create or establish original or new rules of Law known as original precedents. For example a creation of new Law not previously written in the book of Law.
   
• Declaratory Precedents:
  Which merely reiterate and apply an already existing rule of Law are known as declaratory precedents. For example, whatever Law mentioned in the book of Law applies as it is written.
   
• Conditional Authoritative Precedents:
  Decisions made by the smallest bench of High Courts may or may not apply to the same High Courts divisional bench.

Types of judicial decisions:

It can be divided into two parts such as follows:

• Ratio Decidendi/ Reason of Decision:
  It literally means "rules of Law or ruling or knowing the Law". Not only bind the parties but also form the Law for the further generation. The Apex Court furnished the various reasons on which the decision was given in a particular case of ratio decidendi; the facts of the 2 cases, previous and present must be identical, material and relevant; otherwise ratio decidendi is not applicable in the subsequent case. In the case of Dharmodas Vs. Mohori Bibee Courts held that the general principle for minor contracts is void ab initio applied by the subordinate Courts.
   
• Obiter Dicta/Said by the Way:
  It refers to parts of the judicial decisions which are general observations of the judges and do not have any binding authority. Not essential for reaching the decision. A Dictum is given by the way and binds only the parties and does not amount to Law and hence, not bind the future generations. However, the obitor of a higher judiciary is given due consideration by lower Courts and has persuasive value. In the case of Swaran Singh Lamba Vs. Union of India 1995 the Courts held the same.

Circumstances where the binding force of Precedents were challenged:

• Ignorance of statutes;
• Inconsistency between earlier decision of higher Court;
• Precedent sub silentio;
• Decision of equally divided Court;
• Erroneous decision;
• Abrogate decision.

Merits of the doctrine of Judicial Precedents:

• It was judge-made Laws. Therefore they are more practical and realistic.
• It is about scientific development in Law. It brings logical perfection in Law in the form of the principles.
• It brings flexibility in the Law. They mold and shape the Law according to the changed conditions and thus bring flexibility in the Law.
• Bring certainty in Law.
• Based on customs which have been a general practice in the people for a long time.

Demerits of the doctrine of Judicial Precedents:

• A one of the great demerits of this doctrine is the development of Law depends on the incident of motivation.
• Sometimes the conflicting decisions of superior Tribunals throw the judgment of the lower Courts into the harms of a dilemma.
• There is a possibility of overlooking authorities if we follow the precedent.
• An extremely erroneous decision was established as Law was not being brought before the Supreme Court.

Conclusion:
Judicial Precedents is nothing but the process whereby judges follow previously decided cases where the legal issues are sufficiently similar. It is true that it helps to take decisions easily in short time periods. But there is a conflict which makes decisions sometimes erroneous. That is why it needs to be followed very carefully and also the superior Court's responsibility has to give a proper outline of the decisions. Because each and every decision is directly connected to the demands of fair justice by the people of the society.