Thread lifecycle

Hey,

I'm working on an application to scan receipts. When the receipt is saved, It has to be uploaded to a ftp server. I'm using Webclient, and it woked fine, but I don't want the user to wait for the file to be uploaded. I'm considering using a thread, so the upload would run on the background.

My doubt is about the time that thread will be running. When the file is uploaded, the thread is ended? How to manage the memory in that case? The user who scans, does that a thousand times per day, so, I want to be sure about the memory usage by the threads.

Thanks!