# How to Write Technical Documentation in English at Work

> Learn essential English vocabulary and phrases for writing design docs, RFCs, postmortems, and other technical documentation. Includes formal vs. informal register, common mistakes, and pronunciation guide for tech professionals.

- **Author:** Speak Tech English
- **Published:** 2026-08-28
- **Updated:** 2026-09-07
- **Topic:** [Code Reviews & PRs](https://app.speaktechenglish.com/knowledge-base/topic/code-reviews.md)
- **English level:** B2
- **Guide:** https://app.speaktechenglish.com/knowledge-base/how-to-write-technical-documentation-in-english

## Short answer

Technical documentation in English requires mastering document-type vocabulary (RFC, ADR, spec, runbook), process terms (draft, submit, review, iterate), and professional phrases for proposing solutions and acknowledging limitations. Key skills include knowing when to use formal vs. informal register and structuring documents with clear scope, context, and trade-offs.

## Types of Technical Documents You'll Write

Just as academics write different types of papers for different purposes, tech professionals produce various document types. Knowing the right term signals professionalism and helps your team understand the scope and formality of what you're sharing.

| Term | Meaning | Example |
| --- | --- | --- |
| README | Quick-start guide for a repo or tool; helps new users get oriented | 50–500 words |
| One-pager | Brief proposal or summary to get alignment before deeper work | 1 page / 300–600 words |
| Spec (specification) | Detailed requirements for a feature or system; often handed to implementers | 1,000–3,000 words |
| Spike | Time-boxed investigation to reduce uncertainty; documents findings and recommendations | 500–1,500 words |
| Design doc | Proposes a technical approach, explains trade-offs, and invites feedback | 2,000–5,000 words |
| RFC (Request for Comments) | Formal proposal for cross-team or org-wide review; similar to design doc but broader scope | 2,000–6,000 words |
| ADR (Architecture Decision Record) | Records a specific architectural decision and its rationale for future reference | 300–800 words |
| Runbook | Step-by-step guide for operating or troubleshooting a system | 500–2,000 words |
| Postmortem | Analysis of an incident: what happened, why, and how to prevent recurrence | 1,000–3,000 words |

> **Spec vs. Spike vs. One-Pager:** A **spec** says *what* to build with detailed requirements. A **spike** is an investigation to *figure out* if something is feasible. A **one-pager** is a lightweight summary to *get buy-in* before investing more time. Use the right term so stakeholders know what to expect.

## Documentation Process Vocabulary

Writing technical documents involves a clear workflow. Understanding process vocabulary helps you communicate status and next steps to your team.

| Term | Meaning | Example |
| --- | --- | --- |
| draft (n. / v.) | An early version of a document; to write an early version | I'm still drafting the design doc—it's not ready for review yet. |
| iterate (v.) | To revise and improve through multiple cycles | Let's iterate on the proposal after we get initial feedback. |
| circulate (v.) | To share a document with stakeholders for input | I'll circulate the RFC to the platform team tomorrow. |
| submit (v.) | To formally hand in a document for review or approval | Please submit your design doc by Friday EOD. |
| deadline (n.) | The date by which something must be completed | The deadline for ADR comments is next Wednesday. |
| feedback (n.) | Comments and suggestions from reviewers | I incorporated all the feedback from the security review. |
| sign off (v. / n.) | To formally approve; formal approval | We need sign-off from the tech lead before implementation. |
| ship (v.) | To finalize and publish (informal) | Let's ship this runbook so the on-call team can use it. |

Process Terms in Context

- Could you **draft** the postmortem and **circulate** it by Thursday?
- We've **iterated** on the design doc three times based on reviewer **feedback**.
- Once the tech lead **signs off**, we can **submit** the RFC to the architecture review board.
- The **deadline** for the spec is tight, so I'm going to **ship** a first draft today and improve it later.

## Formal vs. Informal Register: Slack vs. Design Docs

Tech culture often blends casual communication (Slack, standups) with formal documentation. Knowing when to shift register is essential. A design doc requires a more formal tone than a quick Slack message, even if you're saying similar things.

| Term | Meaning | Example |
| --- | --- | --- |
| Proposing an idea | I think we should try X | This document proposes X as the recommended approach |
| Acknowledging uncertainty | Not 100% sure yet | This area requires further investigation |
| Asking for feedback | LMK what you think | Feedback is welcome, particularly on sections 3 and 4 |
| Describing a problem | This thing keeps breaking | The current implementation exhibits intermittent failures |
| Stating a limitation | We can't do Y | Y is out of scope for this proposal |
| Referencing sources | Saw it in that doc somewhere | As documented in [link], the system currently... |

> **When to Use Which Register:** Use **informal register** in Slack, quick syncs, and internal team chat. Switch to **formal register** for design docs, RFCs, postmortems, and any document that might be read by people outside your immediate team or referenced months later.

## Common Mistakes: Heard-at-Work vs. Better English

Non-native speakers often make subtle errors that can confuse readers or sound unprofessional. Here are common mistakes heard in tech workplaces and how to fix them.

| Term | Meaning | Example |
| --- | --- | --- |
| I will make a research on this | I will research this / I will investigate this | 'Research' is a verb; no need for 'make a' |
| Please give me a feedback | Please give me feedback / Please share your feedback | 'Feedback' is uncountable—no 'a' |
| We need to discuss about the trade-offs | We need to discuss the trade-offs | 'Discuss' doesn't take 'about' |
| I already submitted the document yesterday | I submitted the document yesterday | 'Already' is often unnecessary with past tense + time marker |
| According to me, we should use Kafka | In my view / I believe we should use Kafka | 'According to me' sounds unnatural |
| The deadline is until Friday | The deadline is Friday / The deadline is by Friday | 'Until' doesn't work with deadlines |
| I will revert back to you | I will get back to you / I will follow up | 'Revert' means return to a previous state (like git revert) |

Fix the errors in these sentences from technical documents.

## Scenario: Drafting a Postmortem After an Incident

Postmortems (also called incident retrospectives or post-incident reviews) are critical documents that analyze what went wrong and how to prevent recurrence. They require precise, blameless language.

| Term | Meaning |
| --- | --- |
| root cause | The fundamental reason the incident occurred |
| contributing factor | A condition that made the incident worse or more likely |
| blast radius | The scope of impact—how many users/systems were affected |
| time to detection (TTD) | How long before the team noticed the problem |
| time to resolution (TTR) | How long to fix the issue once detected |
| action item | A specific task to prevent recurrence |
| blameless | Focusing on systems and processes, not individual fault |

Postmortem Phrases in Context

- The **root cause** was a misconfigured load balancer that failed to route traffic correctly.
- A **contributing factor** was the lack of automated alerting for this failure mode.
- The **blast radius** was limited to 5% of users in the EU region.
- **Time to detection** was 23 minutes; **time to resolution** was 47 minutes.
- **Action item**: Add integration tests to catch configuration drift before deployment.
- This postmortem is **blameless**—we focus on systemic improvements, not individual errors.

> **Cultural Note: Blameless Culture:** In healthy engineering cultures, postmortems avoid blaming individuals. Instead of writing 'John deployed bad code,' write 'The deployment process did not catch the configuration error.' This encourages honesty and learning.

## Scenario: Writing a Design Doc or RFC

Design docs and RFCs propose technical solutions and invite feedback. They require clear structure and professional phrases to present options, trade-offs, and recommendations.

| Term | Meaning |
| --- | --- |
| Stating the problem | This document addresses the problem of... |
| Proposing a solution | The proposed approach is to... |
| Presenting alternatives | We considered the following alternatives: |
| Explaining trade-offs | The trade-off is that X provides Y but at the cost of Z. |
| Acknowledging limitations | This proposal does not address... / Out of scope: |
| Requesting feedback | Feedback is requested on the following areas: |
| Citing prior work | As documented in [RFC-123], the current system... |
| Summarizing a decision | Based on the above analysis, the recommendation is to... |

Design Doc Sentences

- **This document addresses the problem of** slow API response times under high load.
- **The proposed approach is to** introduce a caching layer using Redis.
- **We considered the following alternatives:** in-memory caching, CDN-based caching, and database query optimization.
- **The trade-off is that** Redis adds operational complexity but significantly reduces latency.
- **Out of scope:** This proposal does not cover cache invalidation strategies for real-time data.
- **Feedback is requested on** the chosen TTL values and failover behavior.

Complete these design doc sentences with appropriate phrases.

## Pronunciation Guide for Documentation Terms

Some technical documentation terms are commonly mispronounced. Here's a guide to help you sound confident in meetings and reviews.

> **Memory Trick: Mnemonics for Tech Writing:** A **mnemonic** is a memory aid. For example, to remember design doc sections: **CPTAR** = Context, Problem, Trade-offs, Alternatives, Recommendation. Creating mnemonics for your team's document templates can help everyone stay consistent.

## Practice Exercises

Match each document type to its primary purpose.

Choose the best option for each question.

_This guide has interactive exercises on the page: https://app.speaktechenglish.com/knowledge-base/how-to-write-technical-documentation-in-english_

## FAQ

### What is the difference between a design doc and an RFC?

A design doc typically proposes a technical approach for your team or a specific project. An RFC (Request for Comments) is usually more formal and is circulated for broader, cross-team or organization-wide review. Some companies use the terms interchangeably.

### How do I know when to use formal vs. informal English in documentation?

Use informal register for Slack messages, quick syncs, and internal team chat. Switch to formal register for design docs, RFCs, postmortems, and any document that might be read outside your team or referenced months later.

### What is a blameless postmortem?

A blameless postmortem focuses on systems and processes rather than individual fault. Instead of saying 'Alice caused the outage,' you would write 'The deployment pipeline did not catch the error.' This encourages honesty and learning.

### How do you pronounce 'postmortem' correctly?

Postmortem is pronounced /poʊstˈmɔːrtəm/, with stress on the second syllable (MOR). It comes from Latin meaning 'after death' and is used in tech to mean an analysis after an incident.

### What should I include in a design doc?

A good design doc typically includes: Context (background), Problem statement, Proposed solution, Alternatives considered, Trade-offs, and a clear Recommendation. Many teams use the mnemonic CPTAR to remember these sections.

### Is 'feedback' countable or uncountable in English?

Feedback is uncountable in English. Say 'give me feedback' or 'share your feedback,' not 'give me a feedback.' You can say 'a piece of feedback' if you need to refer to a single comment.


## Related

- [How to Use Suffixes for Technical Vocabulary in English at Work](https://app.speaktechenglish.com/knowledge-base/how-to-use-suffixes-for-technical-vocabulary-in-english.md)
- [How to Build Compound Tech Terms in English at Work](https://app.speaktechenglish.com/knowledge-base/how-to-build-compound-tech-terms-in-english.md)
- [How to Present Technical Ideas Clearly in English at Work](https://app.speaktechenglish.com/knowledge-base/how-to-present-technical-ideas-clearly-in-english.md)
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