Dogs come in all shapes and sizes - the UK Kennel Club recognises 221 different pedigree dogs, from Affenpinscher to Yorkshire Terrier (there are sadly no dog breeds starting with the letter ‘z’!).
Then there are all manner of crossbreeds, from so-called ‘designer dogs’ to lovable mongrels.
Each has its own list of positive and negative attributes, and it’s important to take plenty of time to think about what breed will fit into your lifestyle the best - for instance a smaller dog if you live in a flat, or a hypoallergenic dog if the mere mention of dog hair makes you think about sneezing.
There is even scientific research to guide you, in particular psychologist Stanley Coren’s groundbreaking book The Intelligence of Dogs.
One thing you should consider is that some breeds are more likely to be aggressive than others.
Before they were domesticated, dogs had to fight for everything from food to territory – so signs of aggression were essential to their survival.
Many of these has been bred out to create the perfect family dogs we know today, but other retain the wilder characteristics.
There can be good reason for this – for example for those used as service or guard dogs – but prospective owners should be aware that this is the case before choosing to welcome a certain dog into their homes.
It should also be said that individual dogs may display attributes that are unusual for their breed, and all dogs have the potential to be aggressive in certain situations.
That said, here are the 12 breeds that tend to be placid pets.
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5. Newfoundland
The huge Newfoundland is the very definition of a gentle giant. Their lack of aggression means that they are known as 'nanny dogs' due to their gentle nature and the fact that they get on so well with young children. | Canva/Getty Images
6. Basset Hound
It takes serious amounts of energy to be aggressive - reserves that the notoriously lazy Basset Hound will be loath to dip into unless really needed. | Canva/Getty Images
7. Bernese Mountain Dog
It would be a pretty big problem if the enormous Bernese Mountain Dog was an aggressive breed - thankfully they are another breed of monumental dog who are gentle giants. They are particularly gentle with children and make wonderful family pets - as long as you have enough room and enough cash to pay for all that food! | Canva/Getty Images
8. Beagle
They can often be mischievous, noisy and boisterous - even thoroughly badly behaved - but the Beagle is rarely aggressively naughty. | Canva/Getty Images