Choosing Appropriate Storage

This lesson covers how to choose the right storage technology for a given scenario, considering factors such as capacity, speed, portability, durability, and cost. This is part of OCR J277 Section 1.2.2.

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Factors to Consider When Choosing Storage

When selecting a storage device, you must weigh up five key factors:

Factor	What It Means	Questions to Ask
Capacity	How much data can the device store?	How large are the files? How many files need storing?
Speed	How fast can data be read from or written to the device?	Is fast access important for this task?
Portability	How easy is it to transport the device?	Does the device need to move between locations?
Durability	How resistant is the device to physical damage?	Will the device be used in harsh conditions or while moving?
Cost	How much does the device cost (initial price and cost per GB)?	What is the budget?

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Applying the Factors to Different Storage Types

Magnetic (HDD)

Factor	Rating
Capacity	Excellent — up to 20+ TB
Speed	Moderate — 100-200 MB/s
Portability	Moderate — portable HDDs exist but are bulky
Durability	Poor — moving parts can be damaged by shocks
Cost	Excellent — lowest cost per GB

Best for: Large backups, file servers, storing media libraries, desktop storage where speed is not critical.

Optical (CD/DVD/Blu-ray)

Factor	Rating
Capacity	Low — 700 MB (CD) to 25 GB (Blu-ray)
Speed	Slow — much slower than HDD or SSD
Portability	Excellent — discs are small, lightweight, and easy to transport
Durability	Moderate — can be scratched; sensitive to heat and sunlight
Cost	Very low per disc

Best for: Distributing software or media, archiving small amounts of data, portable data transfer where the recipient has an optical drive.

Solid-State (SSD / Flash)

Factor	Rating
Capacity	Good — 120 GB to 8 TB (SSDs); smaller for USB drives
Speed	Excellent — 500-7,000 MB/s
Portability	Excellent — USB drives and SD cards are tiny
Durability	Excellent — no moving parts
Cost	Moderate to high — more expensive per GB than HDD

Best for: Operating system drives, laptops (durability matters), portable file transfer (USB drives), cameras and phones (SD cards).

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Scenario-Based Practice

Scenario 1: A photographer needs to store thousands of high-resolution photos