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Glossary

Co-founder glossary: domains, money, equity and team rules

81 terms that co-founders and small project teams run into, in plain English. Each one has a short definition and a link to the guide or tool that goes deeper.

By Matt Warcholinski, co-founder of Brainhub · Updated 15 November 2026

General definitions, not legal advice. Rules differ by country, provider and agreement. For anything that involves ownership, equity or tax, check with a professional.

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All terms, A to Z

Domains and DNS

The terms behind owning, moving and keeping a domain name.

Registrant

The person or company listed as the holder of a domain name. The registrar treats the registrant as the owner, not whoever set the domain up or pays for it.

See: Who owns the domain when co-founders split

Registrar

The company where you register and manage a domain. You can move a domain from one registrar to another. Each registrar has its own settings pages and transfer steps.

See: Transfer a domain from GoDaddy, Transfer a domain from Namecheap, Transfer a domain from Cloudflare

Domain transfer

Moving a domain to another registrar, or changing the registrant to a different person or company. These are two separate actions with different steps, so check which one you need before you start.

See: Who owns the domain when co-founders split, Handover checklist

Domain lock

A registrar setting that blocks a domain from being moved to another registrar. It protects against unauthorised transfers. You normally unlock the domain before you start a transfer.

Auth code

A secret code from the current registrar that the new registrar asks for to accept a transfer. Also called an EPP code. Treat it like a password and give it only to the registrar receiving the domain.

WHOIS and RDAP

Public lookup services that show registration data for a domain, often with personal details hidden. RDAP is the newer protocol meant to replace WHOIS. A lookup usually shows the registrar and the expiry date, which is enough to find out where a domain lives.

See: Domain safety check

DNS

The system that turns a domain name into the addresses of your website, email and other services. The settings are called DNS records. They live at a DNS host, which may not be your registrar.

DNS record

One entry in a domain's DNS settings. An A record points the name to a server, an MX record says where email goes. If the records are lost or changed by mistake, the site or the email can stop working.

Nameserver

A server that holds the DNS records for a domain. The registrar's settings say which nameservers a domain uses. Changing them moves control of the DNS to another provider.

TTL

Time to live. It says, in seconds, how long other systems may keep an old DNS answer before asking again. Lowering the TTL before a change makes the change spread faster.

Auto-renew

A setting that renews a domain or a subscription before it expires. It only works if the payment method is valid and someone reads the reminder emails. Note the renewal date even if auto-renew is on.

See: Side project budget planner

Renewal date

The day a domain or subscription must be paid again. Yearly renewals are easy to forget because they come once a year. Write each one next to the cost, and name who pays.

See: Project ledger

Accounts and access

Who can log in, who can recover, and what happens when someone leaves.

Account owner

The person with top-level control of an account, including billing and deletion. Many services allow only one owner, so who it is matters.

See: Access audit

Admin

A user who can manage settings and members. An admin may not control billing or be able to delete the account. What an admin can do depends on the service.

See: Does a second admin protect you?

Backup admin

A second person with enough rights to run and recover an account if the owner is unavailable. Listing someone as a backup does not prove they can recover it. Test it.

See: Does a second admin protect you?, Bus factor

Recovery email

The address a service uses to reset access to an account. If it is one person's private inbox, that person is a single point of failure.

See: Access audit

Recovery code

A backup code you save in advance so you can sign in without your second factor, for example after losing a phone. Most services let each code be used once. Store them where the other person can reach them in an emergency.

Two-factor authentication

A second proof of identity next to the password, such as a code from an app or a hardware key. Often shortened to 2FA. If the one phone that holds the codes is lost, 2FA can lock the whole team out.

See: Access audit

Password manager

A tool that stores passwords and lets a team share some of them in a shared vault. It is a safer way to share access than a chat message. Keep recovery codes in it too.

Least privilege

Giving each person only the access they need for their role. It limits damage from mistakes and makes offboarding simpler.

See: User access review checklist

User access review

A regular check that each person's access still matches their role, and that nobody keeps access they no longer need.

See: User access review checklist

Offboarding

Removing a person's access and moving everything they own to someone else when they leave. Start with the accounts that cost money or hold customer data.

See: If a co-founder leaves, Handover checklist

Handover

Passing a project, an account or a responsibility to someone else, with proof that the new person can act. A handover is finished when the new person has done the task, not when the old one has explained it.

See: Project handover document, Handover checklist

Single point of failure

One person or one thing the project cannot run without. A domain registered only under one person's login is an example.

See: Bus factor

Bus factor

The number of people who could be gone before a project stops. In a two-person project it is often one. To lower it, check that the other person can really do each job.

See: Bus factor guide

Repository

The place where a project's code and its history are stored. On a hosting service it belongs to a user or to an organisation.

Organisation account

A shared account on a service such as GitHub that owns repositories, so that no single person owns the code. Moving a project's repositories into one is a common first step for a team.

Personal access token

A key that lets a script or tool act as a user on a service without a password. Tokens tied to one person can stop working when that person leaves, so note where they are used.

Facebook Page admin

A person with a role on a Facebook Page. Page roles have different powers, and a Page with only one full admin is fragile.

See: Remove an admin from a Facebook Page

Money and costs

Planning, logging and settling shared costs.

Ledger

A running record of costs: what was bought, who paid, how much and when. A ledger shows actual payments, not plans.

See: Project ledger

Shared expense

A cost the project needs and the partners split, such as a domain, hosting or a software plan. Personal tools stay out.

See: Split SaaS costs between co-founders

Split ratio

The share of each cost that each person pays, for example 50/50 or 70/30. Agree it once and write it down. If the split changes, record the date it changed.

See: Cost split calculator

Settle up

Paying the balance so nobody owes anyone. Settle from real payments, not from the budget, because prices change and bills arrive late.

See: Cost split calculator

Reimbursement

Paying back a person who covered a project cost from their own money. Keep the invoice and note the date.

Monthly equivalent

A yearly cost divided by 12, so it can be compared with monthly costs. It is a planning number. The yearly bill still arrives in one piece.

See: Side project budget planner

Yearly cash due

What you will actually pay over twelve months. In the month a yearly bill lands, cash out is higher than the monthly equivalent suggests.

See: Side project budget planner

Budget

The amount you plan to spend, set before you commit. A budget has a cap and is reviewed at milestones.

See: Side project budget planner, Project charter

Spending limit

An amount above which both partners must agree before anything is paid. Choose your own line and write it in the team charter.

See: Team charter

Burn rate

The money a project spends each month. If you have income, use the net amount: spending minus income.

Runway

How many months the money lasts at the current burn rate. It is the cash you have divided by the monthly burn.

SaaS

Software as a service: software you pay for by subscription instead of owning it. Hosting, design tools and AI plans are typical examples for a small project.

See: Split SaaS costs between co-founders

Subscription

A cost that repeats, monthly or yearly. List each one with its renewal date, who pays and how to cancel.

See: Project ledger

Invoice and receipt

An invoice is a request for payment. A receipt is proof that you paid. Keep both for shared costs, because they show who paid and when.

Multi-currency costs

Costs paid in different currencies. Log each in its own currency. If you want one total, convert at a rate you both agree on and note the date.

See: Side project budget planner

Equity and agreements

Ownership, earning it over time and writing it down.

Co-founder

A person who starts a project or company together with others and shares its risks and rewards. Being a co-founder says nothing about who owns what. That needs an agreement.

See: Founders agreement template

Founders agreement

A written agreement between co-founders about shares, roles, costs, accounts and what happens if someone leaves. For a side project it can be one page. It is not a substitute for legal advice.

See: Founders agreement template, Side project with a partner and no company

Equity

Ownership in a company, usually held as shares. Before a company exists, people split a project informally, and that split should still be written down.

See: Equity split calculator

Share

One unit of ownership in a company. A person's percentage is their shares divided by all shares.

Equity split

How ownership is divided between founders. There is no universal right split. Contributions, time, money and risk all play a part.

See: Equity split calculator

Sweat equity

Ownership earned with work instead of money. It needs clear terms, because work is hard to value after the fact.

See: Sweat equity explained

Vesting

Earning ownership over time instead of receiving it all at once. If a person leaves early, they keep only what has vested. The terms are set in the agreement.

See: Founder vesting explained

Cliff

A minimum period that must pass before any ownership vests. A common setup is a one-year cliff inside a four-year schedule, but the numbers are a choice, not a rule.

See: Founder vesting explained

Good leaver and bad leaver

Terms in some agreements that decide what a departing person keeps depending on why they leave. What counts as each is defined in the agreement, so it needs to be written clearly.

See: If a co-founder leaves

Cap table

A table that shows who owns how much of a company. It changes when new shares are issued or when someone's shares vest.

Dilution

The drop in a person's ownership percentage when new shares are issued to someone else. Their share count stays the same, but the total grows.

Shareholder agreement

An agreement between the owners of a company about how it is run and what happens if an owner leaves or sells. It applies once a company exists.

See: Founders agreement template

Partnership agreement

An agreement between partners who run a business together. Rules differ by country and by the form of the business, so get advice before relying on a template.

See: Side project with a partner and no company

Intellectual property

Creations that can be owned, such as code, designs, a brand name or content. Who owns the IP in a project is not automatic. It should be written down.

IP assignment

A written transfer of ownership of intellectual property from one person to another, for example from a founder to the company. Without one, the author may keep the rights, depending on local law and any employment terms.

See: Co-founder dispute and access

License

Permission to use something without owning it. Open source code comes with a license that says what others may do with it.

NDA

Non-disclosure agreement: a promise not to share certain information. Use one when you share something sensitive with someone outside the project.

Bootstrapping

Building a business with your own money and revenue, without outside investment.

Side project

A project you work on next to a job or studies, often with a partner. Money, code and accounts can still become shared, so agree on them early.

See: Side project with a partner and no company

Hackathon

A short event where teams build a project in a day or a weekend. Ownership of the result, the costs and the accounts need agreeing before the event ends.

See: Hackathon kit, Hackathon checklist

MVP

Minimum viable product: the smallest version of a product that you can put in front of real users to learn from. It is a test, not a finished product.

See: Project charter

Team rules and planning

How a small team decides, assigns work and stops.

RACI

A table that shows, for each task, who is Responsible (does it), Accountable (answers for it), Consulted (gives input) and Informed (is told). There is one A per task.

See: RACI matrix template, Responsibility matrix for small teams

Accountable

The one person who makes the final call on a task and answers for the result. Two accountable people on one task usually means nobody is.

See: RACI matrix template

Team charter

A short agreement about how a team works: who decides, how money is approved, and how disagreements are handled. It is about the people.

See: Team charter template, Team charter vs project charter

Project charter

A short document that defines a project before work starts: goal, scope, deliverables, budget, milestones, risks and a stop rule. It is about the work.

See: Project charter template, Team charter vs project charter

Working agreement

Another name for a team charter, common in software teams. It records how the team works together day to day.

See: Team charter template

Decision log

A list of what you decided, why, who agreed and when to review it. Log decisions about money and ownership. Skip small, reversible ones.

See: Decision log template

Scope

What a project includes. A clear scope says what is in and, just as important, what is out.

See: Project charter template

Out of scope

What a project will not do. Writing it down first prevents many arguments later.

See: Project charter template

Deliverable

A thing that exists at the end of a piece of work, such as a live page or a working form. It is checkable: you can say whether it exists.

See: Project charter template

Milestone

A dated checkpoint in a project. Review the budget and the risks at each one.

See: Project charter template

Stakeholder

Anyone affected by a project or able to affect it, such as a customer, a partner or an investor.

Stop rule

A condition you agree in advance that means you stop or change course, such as passing the budget cap. Set it when you are calm, not in the middle of a dispute.

See: Project charter template

Runbook

A short written guide for a recurring task, such as how to deploy or how to renew the domain. It lets another person do the job without asking.

See: Bus factor

Post-mortem

A review after something went wrong, focused on what happened and how to prevent it. It looks at the process, not at who to blame.

Cost-sharing agreement

A written agreement on how project costs are split and settled between partners.

See: Founders agreement template, Cost split calculator

AI and agents

Terms used on the product and developer pages.

MCP

Model Context Protocol: a standard way for AI assistants to use tools and data from other apps. It lets an assistant read or write in a connected service when you allow it.

See: MCP and API

Missing a term?

Tell us which word tripped you up on the contact page. We add terms as we publish new guides and tools.

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