Computer Memory
Computer Memory Introduction
Computer memory is a fundamental component of a computer system. It is where data is stored and retrieved by the processor during operations.
🔹 What is Computer Memory?
Computer memory is a storage space in the computer where data, instructions, and information are stored temporarily or permanently.
🔹 Types of Memory
Primary Memory (Main Memory)
- Directly accessible by the CPU.
- Fast but temporary.
- Examples:
- RAM (Random Access Memory) – Temporary memory; data is lost when the computer is turned off.
- ROM (Read Only Memory) – Permanent memory; contains startup instructions.
Secondary Memory (Storage Devices)
- Not directly accessed by the CPU.
- Used for long-term storage.
- Examples:
- Hard Disk Drive (HDD)
- Solid State Drive (SSD)
- CD/DVD, USB drive
Cache Memory
- Very fast memory located close to the CPU.
- Stores frequently used data and instructions.
- Faster than RAM but smaller in size.
Virtual Memory
- Part of the hard drive used as temporary RAM.
- Used when RAM is full.
- Slower than actual RAM.
🔹 Memory Units
- 1 Byte = 8 bits
- 1 KB (Kilobyte) = 1024 Bytes
- 1 MB (Megabyte) = 1024 KB
- 1 GB (Gigabyte) = 1024 MB
- 1 TB (Terabyte) = 1024 GB
🔹 Memory vs Storage
| Feature | Memory (RAM) | Storage (HDD/SSD) |
|---|---|---|
| Speed | Fast | Slower |
| Volatility | Volatile | Non-volatile |
| Usage | Active processing | Long-term storage |
| Example | Running programs | Saving files |
✅ Key Takeaways
- Memory helps the CPU run programs smoothly.
- RAM is fast but temporary.
- ROM holds important permanent data.
- Storage keeps data safe even when the computer is turned off.
