Introduction
Zoho is a popular cloud-based software company offering a range of business products. To work at Zoho, you need to pass the interview process.

In this article, we'll cover some common Zoho interview questions & what you can expect.
Beginner-Level Zoho Interview Questions
1. What is a software bug?
A software bug is an error or flaw in a computer program that causes it to behave awkwardly or produce incorrect results. Bugs can occur due to mistakes in the source code, design flaws, or issues with how the software interacts with other systems.
Some common types of software bugs include:
- Syntax errors: Mistakes in the code that violate the programming language rules
- Logic errors: The code runs but does not work as intended
- Runtime errors: Issues that cause the program to crash or freeze during execution
- Security vulnerabilities: Weaknesses that attackers can exploit
2. What is a Data Structure?
A data structure is a way of organizing & storing data in a computer so that it can be accessed & modified efficiently. It provides a logical structure for holding data values, establishing relationships between them, & defining permissible operations.
Some common data structures include:
- Arrays: Stores a fixed-size collection of elements of the same data type
- Linked Lists: Consists of nodes where each node contains data & a reference to the next node
- Stacks: Follows the Last-In-First-Out (LIFO) principle for insertion & deletion
- Queues: Follows the First-In-First-Out (FIFO) principle for insertion & deletion
- Trees: Hierarchical structure with nodes connected by edges
- Graphs: Set of vertices connected by edges for representing relationships
- Hash Tables: Uses a hash function to map keys to indexes for fast retrieval
3. What do you mean by recursion?
Recursion is a programming technique where a function calls itself directly or indirectly to solve a problem by breaking it down into smaller subproblems. The function keeps calling itself until it reaches a base case, which is a condition that stops the recursion.
An example of a recursive function to calculate the factorial of a number in C++:
int factorial(int n) {
if (n == 0) {
return 1; // base case
}
else {
return n * factorial(n - 1); // recursive call
}
}
Recursion can be a powerful tool for solving complex problems, especially those that have a repetitive structure or can be divided into smaller instances of the same problem. However, it's important to define the base case correctly to avoid infinite recursion & ensure the function terminates.
4. What is a hashing function?
A hashing function is a mathematical algorithm that takes an input (or "key") & maps it to a fixed-size output called a hash value or hash code. The main purpose of a hashing function is to efficiently store & retrieve data in a data structure called a hash table.
Some key properties of a good hashing function are:
- Determinism: The same input always produces the same hash value
- Efficiency: Computation of hash value should be fast
- Uniformity: Hash values should be evenly distributed across the output range
- Avalanche Effect: Small changes in input should result in drastic changes in the hash value
Some popular hashing algorithms are MD5, SHA-1, SHA-256, etc.
5. What are the OOPs Concepts?
Object-Oriented Programming (OOP) is a programming paradigm based on the concept of "objects", which can contain data & code. The main principles of OOP are:
- Encapsulation: Wrapping data & functions within a single unit (class) & controlling access to it
- Abstraction: Hiding internal details & showing only essential features of an object
- Inheritance: Creating new classes based on existing ones, forming a hierarchy
- Polymorphism: Objects can take on many forms, allowing a single interface to be used for different types
6. What kinds of joins are there in SQL?
SQL joins are used to combine rows from two or more tables based on a related column. The main types of joins in SQL are:
Join Type | Description |
---|---|
Inner Join | Returns records that have matching values in both tables |
Left (Outer) Join | Returns all records from the left table & matched records from the right table |
Right (Outer) Join | Returns all records from the right table & matched records from the left table |
Full (Outer) Join | Returns all records when there is a match in either left or right table |
Cross Join | Returns the Cartesian product of records from the joined tables |
7. What is a virtual function in C++?
A virtual function in C++ is a member function in the base class that can be overridden by a derived class. It allows for runtime polymorphism, where the actual function that gets called is determined dynamically based on the type of the object.
To declare a function as virtual, the virtual keyword is used in the base class:
class Shape {
public:
virtual double getArea() { return 0; }
};
The derived classes can then override the virtual function with their own implementation:
class Rectangle : public Shape {
public:
double getArea() { return length * width; }
};
When a pointer or reference to the base class calls the virtual function, the version defined in the actual object type is invoked, not the base class version. This allows generic code to work with different derived types.
8. What is normalization in the design of a database?
Normalization is the process of organizing data in a relational database to minimize redundancy & dependency. The goal is to ensure data integrity, reduce data anomalies & improve storage efficiency.
There are several normal forms that represent progressive levels of normalization, like :
- 1NF (First Normal Form): Atomicity of data, no repeating groups
- 2NF: 1NF plus no partial dependencies on composite keys
- 3NF: 2NF plus no transitive dependencies on non-prime attributes
- BCNF (Boyce-Codd Normal Form): Stricter version of 3NF
- 4NF & 5NF: Deal with multi-valued dependencies & join dependencies
Benefits of normalization are :
- Minimizing data redundancy & inconsistency
- Simplifying data modification & avoiding update anomalies
- Improving data integrity by enforcing referential integrity constraints
- Enabling more flexible database design that can accommodate future changes
9. What is a deadlock in operating systems?
A deadlock is a situation in an operating system where two or more processes are unable to proceed because each is waiting for the other to release a resource. It arises when the following four conditions, known as the Coffman conditions, hold simultaneously:
- Mutual Exclusion: At least one resource must be held in a non-sharable mode
- Hold & Wait: A process must be holding at least one resource & waiting for additional resources
- No Preemption: Resources cannot be forcibly taken away from a process, they must be released voluntarily
- Circular Wait: There exists a circular chain of two or more processes, each waiting for a resource held by the next process in the chain
10. What is virtual memory?
Virtual memory is a memory management technique that allows programs to use more memory than is physically available on the computer. Parts of the program's memory that are not currently in use are stored on the disk, while active parts are loaded into physical RAM. The operating system and the CPU's memory management unit work together to manage virtual memory, providing memory protection between programs and ensuring smooth operation.