An Overview of Storage Devices - CompTIA A+ 220-801: 1.5

Hard disk drives

Tracks and cylinders

Solid-state drives (SSD)

Master Boot Record (MBR)

• The first sector of a hard drive 
• Usually only 512 bytes
• Contains:
• Table of primary partitions
• Disk signature
• Directions for starting the operating system

Optical formats

• Small bumps read with a laser beam
• Microscopic binary storage
• CD (Compact Disk)
• 700 megabytes (MB) capacity

• DVD (Digital Versatile Disc)
• 4.7 gigabytes (GB) for single layer
• 8.5 GB for dual-layer

• Blu-ray Disc
• 25 GB for single-layer
• 50 GB for dual-layer

Writing to optical media

• "Burners" don't create bumps
• They darken photosensitive dye
• Compact Disk-ReWritable  (CD-RW)
• DVD Read and Rewritable (DVD-R/RW)
• and Dual Layer (DVD-R DL)
• Blu-ray Disc Recordable (BD-R)
• Blu-ray Disc Recordable Erasable (BD-RE) 

Removable storage- flash memory

External hard drives

Tape drives