In simple words, download is something when you transfer any file, document, data, or media from one location (for example, any other device, server, or cloud) to your computer or device and keep that in your device memory. The downloaded files by default get stored in a hard drive rather than the internal memory. For an example of downloading, we can say, opening any website, receiving emails or messages, purchasing any media file from the internet, etc.
Coming to the term uploading -this can be said as a process of sharing or sending some data, files, or documents to any other device or the internet. For example- sending emails, sharing any post on social media, making videos on youtube, etc.
So, what happens when you try to download or upload something?
It might seem to you that downloading is just a one-step process when someone clicks on that particular link or button, right? But there is a bit more than just clicking.
Whenever the user clicks on a particular link the OS of that device locates the place where the pointer is and sends an event to the browser.
After this, the browser creates an HTTP request which is a GET request. Note that, if it is a GET request then data is normally visible to everyone through the URL but if the user is in an https server, it will encrypt the data and will add a particular header to it.
Now, it goes to a networking stack and the server address included in the header is turned into an IP address which is further constructed into several TCP packets.
Then the process follows something like this:-
TCP packets are sent to the router → to a local network station → to a trunk line → to the network station on the opposite side → reaches the machine/server through the router.
Now, in the case of downloading, the server decrypts the packets and translates those according to some set of rules after getting an HTTP request. Then it finds the necessary file for the request and the user address where it has to be returned, After this, the whole process mentioned above is repeated again but in a recursive manner and thus the user gets the file to their device or in other words, the file gets downloaded.
Steps of Downloading:
Click on the particular link or the icon showing the download option. The file will get downloaded to the systemThe OS normally puts it in the download section. Select or move the file wherever needed
Steps of Uploading:
Open the portal where it has to be downloaded. Select the folder where the exact file is present. Select the file to upload. Click on upload.
We can see downloading and uploading are nothing but opposite of each other.
However, the internet speed needs to be higher in case of downloading than in uploading a file. To normal people downloading or uploading is something just clicking a link and getting the file to their device, it may be a phone or a laptop. The actual function behind it is much more critical than we can ever think. But all these happen just within a fraction of a second.
