**Explanation:**

The Indian Constitution, which was adopted on 26th November 1949, has been amended several times since its inception. The first amendment to the Indian Constitution took place in 1951.

**Reason for the First Amendment:**

The need for the first amendment arose due to certain legal and constitutional challenges faced by the newly independent India. It aimed to rectify some of the issues and loopholes that were identified in the original Constitution.

**Key Features of the First Amendment:**

1. **Land Reform**: One of the significant changes brought about by the first amendment was the insertion of Article 31A. This article allowed the government to acquire private land for public welfare projects such as building infrastructure, without providing compensation to the landowners.

2. **Right to Property**: The first amendment also amended Article 19(1)(f) and Article 31 of the Constitution. These changes restricted the right to acquire, hold, and dispose of property as a fundamental right. The government was empowered to impose reasonable restrictions on property rights in the interest of the general public.

3. **Recognizing Zamindari Abolition**: The first amendment validated the abolition of the zamindari system in various states. The zamindari system was a feudal land tenure system where landowners, known as zamindars, collected rent from tenant farmers.

4. **Agricultural Tenancy**: The amendment also introduced Article 31B, which provided protection to certain agricultural tenancy laws. It shielded selected laws related to agricultural tenancy from any legal challenge on the grounds of violation of fundamental rights.

5. **Compensation for Property**: The first amendment also included Article 31C, which provided immunity to laws that aimed to implement Directive Principles of State Policy. It allowed the government to make laws for social welfare and reform, even if they infringed upon the right to property, without the obligation to provide compensation.

**Conclusion:**

The first amendment to the Indian Constitution was made in 1951 to address various legal and constitutional challenges faced by the newly independent India. It introduced significant changes such as land reform, restrictions on the right to property, recognition of zamindari abolition, protection of agricultural tenancy laws, and immunity to laws implementing Directive Principles of State Policy.