External SSDs:

• Typically refers to drives that sit on your desk and require their own power supply.
  
• May offer higher capacities due to their larger size and space for mulitple drives.
• Might offer built-in features like RAID and NAS compatibility.
• Ideal for demanding workflows that call for higher capacities and higher speeds.

Portable SSDs:

• Typically refers to drives that fit in the palm of your hand and draw power from their data connection.
• Small, lightweight, and rugged with possible drop-, dust-, and water-resistance.
• Ideal for data storage on the go, whether you’re on a business trip or out backpacking.

Thunderbolt is generally the fastest, most versatile technology on the market capable of reaching top speeds, connecting multiple high-res monitors at once, daisy-chaining storage devices, and more — all through a single port.

USB — or Universal Serial Bus — is the most common protocol for transferring data to and from storage devices, connecting accessories such as your mouse and keyboard, and keeping your day-to-day tech charged.

For more information, head to Thunderbolt vs. USB-C.

Ports: The entry point, typically on the back of external SSDs, where you make data transfer connections. Port shapes include USB-C, USB-A, and Micro-B, but they’re also optimized for specific data transfer protocol generations, such as Thunderbolt 3 or USB4.

Connectors: The actual shape of the hardware at either end of a cable, such as USB-C, USB-A, and Micro-B. Corresponds to the shape of ports that you use to make data transfer connections.

Cables: The way you make connections between your storage device and your host device. Cables are optimized for specific data transfer protocol generations, such as Thunderbolt 3 or USB4, but they also need to come with the right connector shapes for your devices’ ports.

For more information, head to Thunderbolt vs. USB-C.