What it is: The hardware profile of an EC2 instance (vCPU, memory, network, sometimes GPU).

What it’s for:

• Match workload needs (compute-heavy, memory-heavy, bursty, etc.).
• Control cost (bigger instance = higher cost).

Common categories (high level):

• General purpose (balanced)
• Compute optimized (CPU heavy)
• Memory optimized (RAM heavy)
• Storage optimized (IO heavy)
• Accelerated computing (GPU)

Exam cues:

• “CPU intensive batch processing” → compute optimized.
• “in-memory cache” → memory optimized.

Hard words:

• *profile* /ˈproʊfaɪl/: cấu hình/đặc tính
• *bursty* /ˈbɝːsti/: tăng vọt theo lúc (không đều)
• *optimized* /ˈɑːptəmaɪzd/: tối ưu