Exam domain 1.3 asks you to compare and contrast storage types and their characteristics. This chapter breaks down the different kinds of storage devices and media types so you can understand why an IT professional picks one over another — and what trade-offs they make. Without this knowledge, you cannot troubleshoot a slow computer, choose the right drive for a server, or pass the FC0-U71 exam.
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A simple way to picture Storage Devices and Media Types
You are a warehouse manager for a busy online grocery delivery service. Your job is to decide where to store every item so that it can be retrieved quickly, safely, and cost-effectively.
Your main storeroom is the 'Hard Disk Drive' (HDD) — a massive room with shelves spinning slowly. It holds everything: pallets of rice, frozen peas, toilet roll. It is cheap per square metre, but if a worker needs a single jar of pasta sauce, the forklift has to travel across the entire room. Retrieval is slow because the forklift (the read/write head) has to physically move to the right shelf and wait for the turntable to spin the right row into position.
For the most popular items — milk, eggs, bread — you keep a small, expensive 'Solid-State Drive' (SSD) cooler right next to the packing station. It has no moving parts. The worker just reaches in and grabs the item instantly. SSDs are faster, quieter, and more durable, but they cost more per gigabyte.
For items that need to travel between warehouses or be accessed remotely, you use a 'cloud storage' service — a third-party logistics firm. You pay them only for the space you use, and you can access the inventory from any location, but you rely on their internet connection and security.
Finally, for critical records like invoices and contracts, you use an 'optical disc' (like a Blu-ray) or 'tape' — a fireproof safe that you write once and read rarely. It is slow to access but very stable and cheap for long-term archiving. Your job is to choose the right storage type for each item based on speed, cost, capacity, and how often it is needed.
Storage is where a computer keeps data when it is not being actively used. The computer's processor (CPU) works with data in memory (RAM), but RAM is temporary and volatile — it forgets everything when the power is turned off. Permanent storage, also called non-volatile storage, holds your files, operating system, and applications even when the machine is switched off.
There are several main types of storage, each with different characteristics: speed, capacity, cost, durability, and portability. The FC0-U71 exam expects you to know the differences between them.
Hard Disk Drives (HDD) An HDD uses spinning magnetic platters and a moving read/write head to read and write data. The platters spin at speeds like 5,400 or 7,200 revolutions per minute (RPM). The head moves across the platter to find the right track, then waits for the platter to spin so the data passes under the head. This mechanical movement makes HDDs slower than other types, especially for random access (picking up small files scattered across the drive). However, HDDs are cheap per gigabyte, so they are still used in budget computers, external backup drives, and servers that need very large capacities.
Solid-State Drives (SSD) An SSD has no moving parts. It uses flash memory chips — the same technology found in USB sticks and smartphone memory. Because there is no physical movement, an SSD can access any piece of data in microseconds. This makes your computer boot up in seconds, launch applications quickly, and feel snappy. SSDs are also more durable than HDDs because they can survive drops and bumps. The trade-off is higher cost per gigabyte, though prices have fallen sharply. There are different form factors for SSDs: the common 2.5-inch SATA SSD that fits in the same slot as a laptop HDD, and the smaller M.2 SSD that plugs directly into the motherboard. M.2 SSDs can use the NVMe protocol, which is even faster than the older SATA interface.
Optical Discs Optical discs include CDs, DVDs, and Blu-ray discs. They store data by burning tiny pits into a reflective layer with a laser. The drive reads the pits by shining another laser and detecting the reflections. These discs are cheap, portable, and durable if handled carefully, but they hold less data than modern HDDs or SSDs (a Blu-ray holds up to 128 GB). They are also slow to read and write. Today, optical discs are mostly used for distributing media (like movies on Blu-ray) or for archiving data that must be stored offline.
Flash Drives and Memory Cards USB flash drives and SD cards are also based on flash memory. They are small, portable, and do not need a separate power source. They are commonly used to transfer files between computers, expand smartphone storage, or boot operating systems. They are slower than internal SSDs but faster than optical discs.
Cloud Storage Cloud storage means storing data on servers owned by a provider like Google, Microsoft, or Amazon, and accessing it over the internet. You do not own the physical hardware. Instead, you pay for the storage you use. Cloud storage is scalable (you can increase space instantly), accessible from anywhere, and often includes automatic backup. The downsides are that you need an internet connection to access your data, you rely on the provider's security, and you may pay recurring fees. Common examples are Google Drive, Microsoft OneDrive, and Dropbox.
Tape Drives Tape drives use magnetic tape in a cartridge. They are extremely slow — to read a file, the drive must spool through the tape until it finds the right position. But tape is very cheap per gigabyte and can last for decades. It is used for long-term backup and archival storage where data is not needed often, such as by large corporations and government agencies.
When choosing storage, IT professionals consider these characteristics:
Speed: How fast can data be read or written? SSDs are fastest, then HDDs, then optical and tape.
Capacity: How much data can it hold? HDDs and tape offer the highest capacities per device.
Cost per gigabyte: How much does each gigabyte of storage cost? HDDs and tape are cheapest; SSDs are more expensive but dropping.
Durability: Will it survive drops, vibration, or magnetic fields? SSDs are most durable; HDDs can be damaged by shock; optical discs can be scratched.
Portability: Can you easily carry it? USB sticks and memory cards are highly portable; internal drives are not.
Volatility: Does it need power to retain data? All the types described here are non-volatile — they hold data without power.
Identify the storage need
Determine what the storage will be used for: operating system, application files, user data, backups, or archiving? This step shapes all subsequent decisions.
Evaluate speed requirements
If the data needs to be accessed frequently and quickly (like a boot drive or active project files), choose an SSD. For rarely accessed archives, an HDD or tape is acceptable.
Calculate capacity and cost
Estimate how much data needs to be stored now and in the near future. Multiply by the cost per gigabyte for each storage type to find the most economical solution.
Assess durability and environment
If the storage will be moved or subjected to vibration (like in a laptop), choose an SSD. For stationary servers in a climate-controlled room, HDDs are fine. For off-site backup, consider cloud or tape.
Choose the interface and form factor
Match the storage device to the available ports and physical space. For desktops, 3.5-inch or 2.5-inch SATA drives are common. For modern laptops and ultra-thin builds, M.2 NVMe is preferred.
Implement and test
Install the storage, partition and format it as needed, then test performance with benchmark tools. Verify that the system recognises the correct capacity and that read/write speeds meet expectations.
An IT professional often has to decide what kind of storage to use in a new computer system or an upgrade. Let us walk through a realistic scenario.
Sarah is the IT administrator for a small marketing agency. The agency has 20 employees, all using desktop computers that are five years old. The computers boot in about three minutes, and employees complain that opening large design files takes too long. Sarah knows the bottleneck is the old HDDs.
Step 1: Sarah checks the current configuration. All desktops have a 500 GB HDD (5400 RPM). She runs a benchmark tool and sees that the random read speed is about 80 MB/s — very slow by modern standards. She also asks the employees about their workflows. The graphic designers need fast access to Adobe files; the accountants mostly use spreadsheets and email.
Step 2: Sarah researches options. She considers replacing every HDD with a 500 GB SATA SSD. The SSDs cost about 50 GBP each. That would cost 1000 GBP for all 20 machines plus labour. Alternatively, she could use a hybrid approach: put a small 256 GB M.2 NVMe SSD in each machine for the operating system and applications, and keep the old HDD for bulk file storage. The NVMe SSDs are faster but more expensive.
Step 3: Sarah evaluates cloud storage. The agency currently stores client files on a network-attached storage (NAS) device in the office. She could move everything to Microsoft OneDrive for Business, which costs 5 GBP per user per month for 1 TB each. That would give employees access to files from home, and backups would be handled automatically. The downside: if the internet goes down, employees cannot access their files.
Step 4: Sarah makes a plan. She decides to:
Replace all 20 HDDs with 500 GB SATA SSDs. This is the fastest upgrade for the money and eliminates the boot-time complaints.
Set up OneDrive sync for the design team so that their working files are also stored in the cloud. This gives them off-site backup without changing their local workflow.
Keep the NAS for archiving completed projects. She will eventually move the NAS to a tape backup schedule for long-term retention.
Step 5: Implementation. Sarah orders the SSDs and schedules the upgrades over two weekends. She uses disk-cloning software to copy the contents of each old HDD to the new SSD, then swaps the drives. When employees come in on Monday, their computers boot in 25 seconds. The design team opens files instantly. The agency is now more productive, and Sarah has reduced future support calls about slow performance.
This real-world example shows how an IT professional chooses storage based on cost, speed, capacity, and the specific needs of the users. The FC0-U71 exam will ask you to make similar decisions in multiple-choice questions.
The FC0-U71 exam tests storage in objective 1.3: 'Compare and contrast storage types and their characteristics.' You can expect multiple-choice questions that ask you to identify the best storage type for a given scenario, or to match a characteristic (like 'fastest read speed') to a type.
Key concepts the exam loves to test:
The difference between HDD and SSD: You must know that SSDs are faster, quieter, more durable, and more expensive than HDDs. The exam might say, 'A user needs a storage drive that can survive being dropped. Which type is best?' The answer is SSD.
Volatile vs non-volatile: You must know that RAM is volatile (loses data without power), and all storage types (HDD, SSD, optical, tape, USB) are non-volatile. The exam might ask trick questions where RAM is listed alongside storage types — do not confuse them.
Optical disc types: You should know the capacities: CD (700 MB), DVD (4.7 GB for single layer, 8.5 GB for dual layer), Blu-ray (25 GB for single layer, 50 GB for dual layer, up to 128 GB for BDXL).
Cloud storage characteristics: Understand that cloud storage is accessed over the internet, is scalable, and has a recurring cost. The exam might ask about hybrid setups (some data local, some in cloud).
Tape storage: Know that tape is slow, high capacity, and cheap — used for backups and archiving, not everyday use.
Form factors: Be familiar with 2.5-inch and 3.5-inch drive sizes, M.2, and the difference between SATA and NVMe (NVMe is faster).
Common trap patterns:
The exam might list 'optical drive' as an option for daily system storage. The correct answer is usually HDD or SSD. Optical is too slow and small for operating systems.
They might ask about 'spindle speed' — this applies only to HDDs. An SSD has no spindle.
They might mix up 'memory' (RAM) and 'storage'. Remember: storage is permanent, memory is temporary.
They might ask which storage type is 'most portable' — the answer is typically a USB flash drive or SD card, not an internal drive.
Definitions to memorise for the exam:
RPM (revolutions per minute): HDD speed measure.
NVMe (Non-Volatile Memory Express): a fast interface for SSDs.
SATA (Serial ATA): an older interface used by both HDDs and SSDs.
Form factor: physical size of the drive (e.g., 2.5-inch, M.2).
Flash memory: non-volatile memory used in SSDs, USB drives, and memory cards.
RAID (Redundant Array of Independent Disks): spreading data across multiple drives for performance or redundancy (covered in a different objective but sometimes linked to storage questions).
Practise by reasoning through scenario-based questions. For example: 'A video editor needs fast access to large project files. Which two storage options are best?' The answer: internal SSD (NVMe) for speed and a NAS with RAID for capacity and redundancy. Understand why, not just the labels.
An HDD uses spinning magnetic platters and a moving read/write head; an SSD uses flash memory with no moving parts.
SSDs are faster, quieter, more durable, and more expensive per gigabyte than HDDs.
Optical discs (CD, DVD, Blu-ray) are slow and low-capacity, used mainly for media distribution and archiving.
Cloud storage is accessed over the internet, is scalable, and has a recurring cost, but it depends on network speed and provider security.
Tape storage is extremely slow but very cheap per gigabyte, used for long-term backups and archives in enterprise environments.
Non-volatile storage (HDD, SSD, optical, tape, USB) retains data when the power is off; volatile storage (RAM) loses it.
Form factors like 2.5-inch, 3.5-inch, and M.2 determine physical size and often the performance interface (e.g., NVMe).
These come up on the exam all the time. Here's how to tell them apart.
HDD
Uses spinning magnetic platters and a moving read/write head
Slower read/write speeds, especially for random access
Cheaper per gigabyte, suitable for bulk storage
SSD
Uses flash memory chips with no moving parts
Much faster read/write speeds, near-instant access
More expensive per gigabyte but costs are decreasing
SATA SSD
Uses the SATA interface (same as HDDs)
Maximum speed around 550 MB/s
Compatible with older systems that have SATA ports
NVMe SSD
Uses the PCIe interface (much faster)
Speeds can exceed 3500 MB/s
Requires a modern motherboard with M.2 slot supporting NVMe
Cloud Storage
Data is stored on remote servers accessed over the internet
Requires recurring subscription or pay-per-use fees
Accessible from anywhere with an internet connection
Local Storage (HDD/SSD)
Data is stored on a physical drive inside or attached to your computer
One-time purchase cost for the drive
Only accessible from the device it is directly connected to
Optical Disc (CD/DVD/Blu-ray)
Read and written using a laser; limited write cycles
Typically slower read/write speeds
Capacities up to 128 GB for Blu-ray; smaller for CD/DVD
USB Flash Drive
Read and written electronically via USB interface
Faster than optical discs, especially for small files
Capacities up to 2 TB or more in a small form factor
Mistake
An SSD is always the best choice for every storage need because it is faster.
Correct
SSDs are faster and more durable, but HDDs offer much lower cost per gigabyte and higher maximum capacities, making them better for bulk storage of files that are accessed infrequently.
Beginners hear 'SSD is faster' and assume it is always superior, without considering cost and capacity trade-offs.
Mistake
Optical discs are completely obsolete and never used in IT.
Correct
Optical discs like Blu-ray are still used for distributing large software packages, playing movies, and for some archival purposes where a write-once, read-many (WORM) medium is required.
Most home computers no longer include optical drives, so people assume they are gone from IT entirely, but they remain in niche enterprise and media-distribution roles.
Mistake
Cloud storage is always faster than local storage.
Correct
Cloud storage speed depends entirely on your internet connection bandwidth and latency. Local SSDs and even HDDs are usually much faster for everyday file access because there is no network delay.
Marketing around 'the cloud' implies speed and convenience, but the physical reality of internet latency makes it slower than local storage for most read/write operations.
Mistake
A USB flash drive is the same technology as an internal SSD, just in a different shape.
Correct
While both use flash memory, USB flash drives typically use cheaper, slower NAND flash and a USB controller that is far slower than the SATA or NVMe controller in an internal SSD. USB drives are fine for file transfers but not as primary system drives.
They look similar (both have no moving parts), so beginners assume they perform equally, but the interface and controller quality make a huge difference.
Mistake
Tape drives are outdated technology that nobody uses anymore.
Correct
Tape drives are still widely used in enterprise data centres for long-term archival backup because they are the cheapest storage per gigabyte, have very low power consumption, and can store decades of data reliably.
Consumers never see tape, so beginners assume it is extinct. In reality, huge amounts of corporate and scientific data are stored on tape.
Reveal each answer, then mark whether you got it right. Score 60%+ to unlock the next chapter.
SSD stands for Solid-State Drive. It uses flash memory chips instead of spinning magnetic platters, so it has no moving parts. This makes SSDs faster, more durable, and quieter than HDDs, but they cost more per gigabyte.
Not exactly. Cloud storage is a place to keep files online, which can serve as a backup if you copy your data there. But a proper backup strategy often includes both cloud storage and local copies (like an external drive) for redundancy.
Yes, in most laptops you can. You need to check the form factor (usually 2.5-inch SATA or M.2) and then clone your existing drive to the new SSD before swapping them. The performance improvement is dramatic.
SATA SSDs use the older SATA interface (same as HDDs), which maxes out around 550 MB/s. NVMe SSDs use the PCIe interface, reaching speeds of 3500 MB/s or more. NVMe is much faster but requires a compatible motherboard slot.
Properly stored, a burnt CD or DVD can last 10 to 20 years. Pressed discs (like commercial movies) can last longer. However, cheap discs may degrade faster. For critical data, consider archival-grade discs or other media.
Tape drives use magnetic tape in cartridges for extremely cheap, high-capacity, long-term storage. They are very slow but perfect for backing up large amounts of data that you do not need to access often, like monthly server backups.
You've finished Storage Devices and Media Types. Continue through the FC0-U71 study guide to build a complete picture of the exam.
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