For many of us, especially those born in the 80s, the word 'pond' might conjure images of small, manmade bodies of water at the bottom of gardens, replete with decorative stone edging, lily pads, perhaps a ruddy fishing gnome.
For those with more flamboyant gardens, they may hear the burble of a water feature and picture a couple of koi swimming about in the water.
Today we're more interested in making sure our garden pond is an important habitat to support threatened British species. These wildlife ponds can attract amphibians, such as common frogs and smooth newts, and ecologically important insects, including damselflies and dragonflies.
Guide to looking after your pond
What is a pond?
Ponds can be naturally forming as well as manmade. They are small, land-based bodies of water that are still and enclosed, rather than connected to a stream or river. They are usually fed by an underground spring or by rainwater. They are mostly freshwater, but sometimes brackish (a mix of saltwater and freshwater).
We have a growing interest in swimming ponds, too, which are much larger. Also know as natural swimming pools, they are bodies of water are designed to mimic natural ponds and lakes but provide a satisfying swimming experience.
But when should we start calling a big pond a lake?
When does a pond become a lake?
Keeper's Pond, a beautiful body of water in Monmouthshire with views over Brecon Beacons National Park, is confusingly described on the Visit Monmouthshire website as a 'lake'.
But which is it?
Many dictionary definitions describe ponds as being simply smaller than lakes, sometimes the difference being arbitrary. Unlike with a hill and a mountain, there doesn't seem to be strict classification criteria.
However, Freshwater Habitats Trust, the UK’s leading charity for all freshwaters, has clearer guidelines:
Ponds can vary in size, between 1 square meter and 2 hectares, and hold water for four months of the year or more.
It says that even temporary or seasonal ponds are great for freshwater wildlife, but they are a highly threatened habitat type.
Keeper's Pond is reported as being 1.48 hectares (15,000 sq m), so officially it is a pond.
What is a lake?
Broadly speaking a lake is a large standing or slow-moving body of water. They are usually fed by springs or rain and snow melt and are fed and drained by rivers and streams.
According to the Wildlife Trusts they come in many forms: "Some are splendid and clear, while others are more reminiscent of a murky swamp. Each lake is strongly influenced by the underlying lakebed and the surrounding landscape."
What's the difference between a lake and a water?
Things get confusing in the north of England when we reach the Lake District. You may have been caught out with the brainteaser: How many lakes are in the Lake District?
The answer is just one official lake - Bassenthwaite Lake, but this is solely because it was given the title of lake when it was originally named. The rest have been named as waters or meres. Generally, a mere is broader and shallower than a lake.
What's the deepest lake in the UK?
Loch Morar is the deepest lake, with a maximum depth of 310m. It's almost exactly the same depth as the height of the UK's tallest building, The Shard in London.
What's the biggest lake in the UK?
Many of the UK's largest lakes are found in Northern Ireland (loughs) and Scotland (lochs). The biggest, at 150 square miles, is Lough Neagh. Its depth averages just 9m.
What about lagoons and tarns?
A lagoon is a small body of water separated by a physical border. Lagoon is often used to describe bodies of water near the sea, for example the Blue Lagoon in Pembrokeshire.
A tarn is a small mountain lake or pond in a hollow area surrounded by steep slopes formed by a glacier, such as Easedale Tarn in Cumbria.
Find out more
The UKs most beautiful lakes
Wild swimming in Britain: best places to swim, water safety and how to get started
Best walks in the Lake District National Park
Britain’s most beautiful rivers
Main image: Getty Images