JAWAHARLAL NEHRU TECHNOLOGICAL UNIVERSITY HYDERABAD B.Tech I Year PROGRAMMING FOR PROBLEM SOLVING Previous Question Paper (June - 2022 - R18)

Computer memory is the electronic storage space in a computer where data and instructions are held for processing. It is categorized based on its accessibility, speed, and volatility.

Primary Memory: Also known as main memory, it is directly accessible by the CPU. It is volatile, meaning data is lost when power is turned off. Examples include RAM (Random Access Memory), which stores currently running programs, and ROM (Read-Only Memory), which stores essential boot-up instructions.

Secondary Memory: This is non-volatile storage used for long-term data retention. It is slower than primary memory but offers much larger capacity. Data is not lost when the computer is powered down. Examples include Hard Disk Drives (HDD), Solid State Drives (SSD), USB flash drives, and optical discs.

Type conversion is the process of converting a value from one data type to another. It is classified into two main types:

1. Implicit Type Conversion (Type Promotion): This is performed automatically by the compiler when compatible data types are mixed in an expression. The smaller data type is promoted to the larger data type to prevent data loss.

2. Explicit Type Conversion (Type Casting): This is performed manually by the programmer using the cast operator. It is necessary when converting a larger data type to a smaller one, which may result in data truncation.

Explicit casting allows the programmer to force a conversion, providing control over how data is interpreted, whereas implicit conversion ensures safety during arithmetic operations between different numeric types.