My MacBooks HDD suddenly filled up. Please help

[lisamel]

Hi!
Well, this morning I checked something on my macbook and I realised that I only have about 19 GB HDD left. Yesterday it was about 50GB.. I havent downloaded more than maybe 1GB.
Does anyone know if I can check what is taking up so much space?

Thanks so much

Lisa

 

[AppleMatt]

Sounds like a runaway log.

Does this shed any light as to what it might be?
Disc Inventory X

AppleMatt

 

[lisamel]

Thanks for that I will have a look!!
My dad did say he would use my laptop to edit a movie from his camcorder, so maybe that is why its almost filled up? If its still in iMovie i mean?