If you're now trying to wrap your head around Ontario's shutdown just as you were getting comfortable with the colour-coded zones, don't panic.

Here's a breakdown of the key terms and definitions you didn't know you'd need to know before the pandemic — and there won't be a pop quiz, we promise. 

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Ontario's provincewide shutdown

Not unlike the shutdown that Ontario implemented in December, the entire province is now back under the same restrictions for a four-week period, starting on April 3, 2021.

These shutdown rules are similar to those in the grey-lockdown zone (we'll get to that later) but more restrictive.

For example, the lockdown zone was recently revised to permit outdoor dining, but it is prohibited during the shutdown.

Under the shutdown, all retailers are allowed to remain open at a limited capacity, while most other businesses including gyms and salons must remain closed.

Emergency brake

Back when the province began to allow regions to gradually reopen, officials introduced their new "emergency brake" system.

This brake allows health officials to swiftly move regions from their colour-coded zone back into the lockdown zone if transmission increases.

In the case of the new shutdown, officials stated that a provincewide emergency brake was activated in response to the third wave.

Stay-at-home order

In January, the premier announced a provincewide stay-at-home order, which prohibited Ontarians from leaving home for non-essential reasons.

Essential trips were defined as accessing goods and services necessary for an individual's safety, health and wellbeing.

These could include outings for groceries, medication, exercise, work or health care. However, the province said that essential reasons vary from person to person, and there is no limit to how many you can take in one day.

Officials made it clear that a stay-at-home order is not being enforced during the current shutdown to encourage people to get outside safely.

State of emergency

The province first declared a state of emergency back in March of 2020, and a second one was declared in January 2021.

The state of emergency allows Ford's government to unilaterally impose new rules such as the shutdown, stay-at-home order and other public health measures.

All emergency measures under the Reopening Ontario Act were recently renewed.

Lockdown

The term lockdown refers to the grey-lockdown zone of the provincial framework.

This zone prohibits indoor gatherings of any size, indoor dining, as well as personal care services, cinemas and gyms. Outdoor gatherings of five people and in-person shopping are permitted.

The zone was recently adjusted to allow patio and outdoor dining to resume and was even poised to allow personal care services to reopen by appointment only on April 12, 2021.

Colour-coded zone framework

The colour-coded zones, a.k.a. the COVID-19 Response Framework, are the various zones that represent the level of reopening permitted in the region.

The five zones are green-prevent, yellow-protect, orange-restrict, red-control and grey-lockdown.

Green is the zone with the fewest restrictions, permitted in areas with the lowest positivity and transmission rates. The levels increase from there.