What is isolation?

Isolation is the practice of keeping one thing separate from others so they don’t interfere with each other. In tech it means making sure a program, a piece of data, or a service runs in its own “bubble” where it can’t accidentally read, change, or crash something else.

Let's break it down

  • Process isolation: each program gets its own memory space.
  • Container/VM isolation: an entire operating system or app runs in a self‑contained environment.
  • Database isolation: transactions are kept separate so one user’s changes don’t mess up another’s view.
  • Sandboxing: risky code is run in a locked‑down area that can’t touch the rest of the system.

Why does it matter?

  • Security: a breach in one area stays limited.
  • Stability: a crash in one app won’t bring down the whole machine.
  • Predictability: results are consistent because nothing unexpected can sneak in.
  • Resource control: each isolated unit can be given a fair share of CPU, memory, or disk.

Where is it used?

  • Desktop and server operating systems (process isolation).
  • Cloud platforms like AWS, Azure, and Google Cloud (virtual machines and containers).
  • Docker, Kubernetes, and other container tools.
  • Database systems such as MySQL, PostgreSQL, and Oracle (transaction isolation levels).
  • Web browsers (each tab or extension runs in a sandbox).
  • Mobile apps (iOS and Android sandbox each app).

Good things about it

  • Keeps malicious or buggy code from harming the whole system.
  • Makes debugging easier because problems are confined.
  • Allows multiple users or services to share the same hardware safely.
  • Enables “pay‑as‑you‑go” cloud pricing by packing many isolated workloads on one server.

Not-so-good things

  • Extra overhead: virtual machines need more CPU and memory than a bare program.
  • Complexity: setting up and managing isolation layers can be tricky.
  • Performance hit: communication between isolated units (e.g., containers) can be slower than direct calls.
  • Possible duplication: each isolated environment may need its own copy of libraries or data, using more storage.