Motorway driving is a skill that can be developed through practice. There are many things to think about, including entering the motorway via slip roads, being aware of your surroundings, using indicators and mirrors, and driving at a safe distance from other .

will also be aware that there are specific rules when it comes to which lane you should be in - and that you shouldn't undertake other drivers.

Undertaking is a term used for a driver passing another vehicle on the left side of a motorway. The Highway Code advises drivers not to undertake, as it can cause accidents.

However, there are certain instances when it is okay to undertake. Taking to page George's Car Media, Owen Messenger, a Sergeant in , Roads Policing, said undertaking is one of the most common things he gets asked about on social media.

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Explaining the only time it's allowed, Owen said: "You can't undertake on the motorway. The only time that you can undertake is when your lane is genuinely moving slower than the other lanes. That's generally when you're going through roadworks, or it's heavy traffic, or something like that."

However, generally you shouldn't be undertaking on the motorway. The sergeant explained that the reason why is because "people aren't expecting you" to approach from the left side, and because people will be looking to move back to the left, which is their "default position on the motorway", it can cause an accident.

"Please don't undertake on the motorway, it's really really dangerous," he added. George, who started the channel and has been working with local police teams to share road safety advice, asked if people can get into trouble for it.

Owen replied: "Well, it's just unnecessary isn't it. The default position [...] is to be in lane one, and if everyone stuck to the rules you wouldn't have everyone darting around all over the place." He added that it was more about "following motorway etiquette" to make everything as safe and efficient as possible.

Although not technically illegal, the Highway Code highly discourages undertaking, and states: "Do not overtake on the left or move to a lane on your left to overtake."

However, there are exceptions, such if a car undertakes in a slow-moving traffic lane which is moving faster than the lane on the right.

Rule 268 of The Highway Code states: "In congested conditions, where adjacent lanes of traffic are moving at similar speeds, traffic in left-hand lanes may sometimes be moving faster than traffic to the right. In these conditions you may keep up with the traffic in your lane even if this means passing traffic in the lane to you right. Do not weave in and out of lanes to overtake."

It may also be acceptable if there's an average speed check, where vehicles are advised to 'stay in lane'. In these situations it may be safe to pass a car travelling below the average speed limit on your right if your lane is moving faster.