Imagine if your favourite TV show could be filmed anywhere! That is what an outside broadcast is. When most TV shows are filmed, they happen inside a big studio with bright lights, cameras, and sets. But sometimes, TV shows need to happen in other places like a sports stadium, concert hall, or a street parade.
When the TV crew films something like a sports game outside of the studio, they need to pack up all their cameras, lights and equipment and take it to the location where the event is happening. Once they get there, they need to set up everything again, like they would have in the studio. Only then they can start to film the TV show just like they would have in the studio.
But filming outside can be tricky because they have to deal with things they wouldn't usually have to think about in a studio. For example, they need to be careful not to get the camera wet if it starts to rain or make sure the sun doesn't shine too bright so that the picture is clear for everyone watching at home.
In summary, an outside broadcast is when a TV show is filmed outside of a studio, usually in a special place like a stadium or concert hall, and the TV crew have to set up their equipment before they can start filming.