> ## Documentation Index
> Fetch the complete documentation index at: https://docs.timetracker.in/llms.txt
> Use this file to discover all available pages before exploring further.
# How TimeTracker works
> The model behind TimeTracker in one page – how clients, projects, tasks, time entries, timesheets, budgets and invoices connect into a single chain.
Most tools give you a time tracker, or a project board, or an invoicing app.
TimeTracker connects all of them, so an hour you record shows up in five places
without you doing anything twice.
This page explains that model. It is the most useful ten minutes you can spend here.
## The chain
Almost everything follows one chain:
**Client → Project → Task → Estimate → Time entry → Approval → Budget impact → Invoice → Payment**
Read it as a sentence:
> You do work for a **client**, on a **project**, broken into **tasks**. You
> **estimate** how long each task should take. People record **time entries**
> against those tasks. A reviewer **approves** that time. The time lands on the
> project **budget**. Approved billable time becomes an **invoice**. The client
> pays, and you record the **payment**.
Every feature in the product is either a link in this chain or a way of looking at it.
## Follow one hour through the system
Here is the same chain with real numbers. Sarah Lin is a designer at Northwind
Studio.
**Bluebird Coffee** is a client – a company Northwind bills.
**Website Redesign** is one engagement for Bluebird, with a **\$40,000** budget.
**Homepage wireframes**, assigned to Sarah, estimated at 8 hours.
She starts the timer on Monday morning and stops it three hours later. That
creates a **time entry** of 3 hours, marked billable.
Sarah's billable rate is **$100/hour**, so the entry is worth **$300**. Her cost
rate is **$45/hour**, so it costs Northwind **$135**. The margin is **\$165**.
That 3 hours appears in Sarah's week automatically. She does not re-enter it.
The Website Redesign budget moves from $0 to **$300 used\*\* of \$40,000.
On Friday she submits. The timesheet moves from **draft** to **submitted**.
Priya (Project Manager) reviews and approves. The time is now **locked** – only
an admin can change it.
At month end, Daniel (Finance) creates an invoice from Bluebird's approved
billable time. Sarah's 3 hours appear as a \$300 line.
Daniel records the payment. The invoice moves to **paid**.
One action by Sarah – starting a timer – fed the timesheet, the budget, the margin,
the report and the invoice. That is the whole idea.
## The building blocks
### Workspace
The workspace is the container. Your team, clients, projects and data all live
inside exactly one workspace, and its name appears in every URL.
You can belong to more than one workspace – an agency and a side business, say – and
switch between them. See [workspaces](/concepts/workspaces).
### Client and project
A **client** is a company you bill. A **project** is one engagement for that client.
One client can have many projects.
Bluebird Coffee is a client. Website Redesign and Monthly Retainer are two projects
for that same client, with different budgets.
### Section and task
A **task** is a unit of work. Tasks live in **sections**, which are the columns or
phases a project defines – "To do", "In review", "Done", or "Discovery", "Design",
"Build". Sections are how a project describes its own workflow.
See [project sections](/projects/project-sections).
### Estimate
An **estimate** is on a task: how long this piece of work should take. It is a
prediction, and comparing it to reality is where you learn.
An estimate is not a budget. See [budget vs estimate](/concepts/budget-vs-estimate).
### Time entry
A **time entry** is the atom of the whole product – one person, one stretch of time,
against one task or project.
You can create it with a timer or type it in afterwards. Both produce the same thing.
Every entry records whether it is **billable**, and freezes the **rate** that applied
when it was recorded. Changing a rate next month never quietly rewrites last month's
numbers. See [rate snapshots](/rates/rate-snapshots).
### Timesheet
A **timesheet** is not a separate thing you fill in. It is your week's time entries
in one grid. Recording time *is* filling in your timesheet.
The timesheet adds one thing: a **submission**, so a reviewer knows the week is
finished. See [how timesheets work](/timesheets/how-timesheets-work).
### Approval
Approval turns "recorded" into "agreed". Once a week is approved, the time is
**locked** – it is now the basis for invoices and reports, so it should not shift
under you.
Approving is a Pro feature. See [approvals](/approvals/overview).
### Budget
A **budget** is a ceiling on a project: either **hours** or **money**, either
**one-time** or **monthly** for a retainer. Time entries consume it as they are
recorded.
See [how budgets work](/budgets/how-budgets-work).
### Invoice
An **invoice** turns approved billable work into a bill. It moves through its own
states – draft, sent, viewed, partially paid, paid, overdue, void – and each state
decides what you may still edit.
See [invoice statuses](/invoicing/invoice-statuses).
## The two numbers on every hour
This is what makes TimeTracker different from a plain time tracker. Every hour
carries **two** rates:
| Rate | Meaning | Who sees it |
| ----------------- | ----------------------------------- | -------------------------------- |
| **Billable rate** | What you charge the client per hour | Anyone with `rate.viewBilling` |
| **Cost rate** | What that hour costs you | Only people with `rate.viewCost` |
Revenue minus cost is **margin**. Because both numbers ride on every entry, you can
see a project's profitability while it is still running, not after you invoice it.
Sarah's 3 hours: $300 revenue, $135 cost, \$165 margin.
Cost is deliberately walled off. A Project Manager can see what you charge without
seeing what you pay people. See [cost rates](/rates/cost-rates).
## The parts that sit beside the chain
Not everything is a link in the chain. These run alongside it.
| Area | What it adds |
| ------------------------------------- | --------------------------------------------------------------------------------------- |
| [Work schedules](/schedules/overview) | What each person is *expected* to work, so timesheets have something to compare against |
| [Time Clock](/time-clock/overview) | Presence at work – clock in, clock out – separate from hours on a task |
| [Time off](/time-off/overview) | Leave requests, balances and holidays |
| [Resource Planner](/planner/overview) | Planning work *before* it happens |
| [Expenses](/expenses/overview) | Costs that are not hours, which can also be re-billed |
| [Reports](/reports/overview) | Any question you want to ask about the data |
| [Client portal](/portal/overview) | A read-only window for the client |
## Four gates decide what you see
Before any screen appears, four separate checks run:
1. **Is the app switched on?** – [apps](/concepts/apps-and-modules)
2. **Does the plan include it?** – [plans](/concepts/plans-and-features)
3. **Does your role allow it?** – [capabilities](/concepts/roles-and-capabilities)
4. **Is this person or project in your scope?** – [scope](/concepts/supervision-scope)
They fail in different ways. Learning to tell them apart is the fastest way to
answer "why can't I see this?".
## What to read next
Put this into practice in about ten minutes.
The same picture, as a structure.
The full chain, step by step, with real numbers.
Every term, defined once.
## Related guides
* [Workspaces](/concepts/workspaces) – the container everything lives in
* [Billable vs non-billable](/concepts/billable-vs-non-billable) – which hours can be invoiced
* [Rates explained](/concepts/rates-explained) – how an hour gets a price
* [Budget vs estimate](/concepts/budget-vs-estimate) – two numbers people mix up