A gigabyte is a unit of measurement for digital information, equal to roughly one billion bytes. Think of bytes as tiny containers that each hold a single letter, number, or simple instruction. A gigabyte can hold about one billion of these containers, which is enough space to store hundreds of songs, thousands of photos, or several full-length movies.

Computer scientists use gigabytes to measure how much information a device can store or how much data travels across the internet. Your laptop might have 256 gigabytes of storage, while a smartphone might have 64 or 128 gigabytes. When you download a video game that's 20 gigabytes, you're using up about 20 billion bytes of storage space.

Gigabytes help us understand digital capacity the way gallons help us understand how much a bucket holds. Just as you might say a pool holds thousands of gallons, you might say your tablet can store 32 gigabytes of apps, videos, and documents. When someone warns that your phone is “running out of gigabytes,” they mean you're filling up your available storage and might need to delete old files to make room for new ones.