upload
To send a file from your device to the internet.
To upload means to send a file or information from your device to the internet or another computer. When you upload a photo to a website, you're transferring it from your phone or computer so others can see it online. When you upload a video to YouTube or turn in an assignment through your school's website, you're moving that file from your device to a server somewhere else.
Think of it as the opposite of downloading. Downloading is like receiving a package: you're bringing something from the internet to your device. Uploading is like mailing a package: you're sending something from your device out to the internet or another computer.
The process happens through your internet connection. You select the file you want to share, click an upload button, and your computer breaks the file into tiny pieces of data that travel through your internet connection to their destination. Once the upload finishes, that file exists in the new location, though the original usually stays on your device, too.
People upload all kinds of things: documents for work, photos to share with family, videos for others to watch, or homework assignments for teachers to review. Every time you post something online or share a file through the internet, you're uploading it.