Speeding - the minimum penalty for breaking the speed limit is £100 and 3 penalty points added to a licence. If this builds up to 12 points in a 3 year period it can result in disqualification.
Drink driving - the drink drive limits vary between England & Wales and Scotland (which has a lower limit). It is measured as the quantity of alcohol found in the blood, breath or urine and this will differ from person to person and on a variety of factors. Convictions for drink driving can result in fines, driving bans and even imprisonment.
Drug driving - it is illegal to drive with certain levels of illegal drugs in the bloodstream, even if driving ability has not been impaired. Driving with prescription drugs can also be illegal if they have affected driving ability. Penalties include unlimited fines, a minimum of one year driving ban and up to six months in prison. Scotland will be introducing stringent drug driving limits and roadside testing from the 21 October 2019.
Dangerous and careless driving - driving without due care and attention (eg inadvertently driving through a red light) and the more serious offence of dangerous driving (eg deliberately driving through a red light) can both result in penalty points, but dangerous driving can also lead to driving disqualification, fines and prison sentences.
Using phone while driving - it is illegal to hold a phone while driving, even while stationary at traffic lights or in a traffic jam (unless it is to call the emergency services and it is unsafe or impractical to stop). Initial penalties can result in 6 points and a £200 fine, in England and Wales, and 3 points and a £60 fine in Scotland.
Not wearing a seatbelt - subject to limited exceptions (eg whilst reversing), drivers are responsible for wearing their own seatbelt and also of ensuring that any children in their vehicle wear seatbelts. Failure to do so can result in a £500 fine.
Driving without insurance and MOT - drivers can receive a fixed penalty £300 fine and 6 points if they drive on a public road without at least third party insurance. Subject to certain exceptions, cars cannot be driven without a current MOT and drivers can be fined up to £1,000.