What Is A Download?

Date First Published: 28th February 2022

Topic: Computer Networking

Computer Terms & Definitions

Subtopic: Data Transmission Technologies

Difficulty Level: 2/10

Learn more about what a download is in this article.

A download, sometimes shortened to a DL or D/L is a term used to describe a file being copied from a server to another device over the internet. It is the opposite of uploading as this refers to sending a copy of a file to a web server so that it can be accessed by multiple users. It is one of the most common file sharing methods, with the other being uploading.

Downloads occur all the time whilst browsing the internet. Every time a webpage is visited, that webpage, along with any CSS, JS files, and images are downloaded in order for it to be displayed in a web browser. They are then cached and temporarily stored in the web browser in order for pages to be loaded quicker unless an adjustment has been made to the settings of the web browsers for it to not cache webpages. This webpage of the article that you are reading now was downloaded in your web browser in order for it to be displayed.

Note:

Downloads use a small amount of bandwidth, which is equal to the size of the downloaded files from the web server unless they are cached. Downloading programs from the internet uses up a lot of bandwidth, since it usually consists of a zip file with an EXE file that can sometimes be hundreds of megabytes in size. Any type of file can be downloaded, which could include images, videos, programs, webpages, etc.

A download always requires an internet connection in order for it to occur. However, when the file has finished downloading onto the computer, it can be viewed offline, since it is stored on the device and not a server. Downloaded files that are stored locally on a computer are kept permanently unless they are deleted. An easy way to remember the difference between uploading and downloading is:

• Upload = Send. Data from a device, such as a computer, smartphone, or tablet is being sent to another location over the internet, usually a web server. Upload icons are usually represented by arrows pointing upwards, because of the word 'up' in upload.
• Download = Save. Data from another location is being saved onto a device, such as a computer, smartphone, or tablet. Download icons are usually represented by arrows pointing downwards, because of the word 'down' in download.

Download Speed

All downloads have a download speed, which refers to the rate that a file can be copied from a server to a computer. Download speed is measured in megabits per second (Mb/s). The higher the download speed, the quicker a copy of the file will be sent from the server to the computer. Slower download speeds mean that it will take longer. The download speed is mostly based on the ISP and the server and the average download speed is 12-25 Mb/s.

Methods of Downloading

• HTTP - The protocol that is used for the transmission of information between web browsers and servers, and how computers communicate with each other across the World Wide Web. This is the most common way to download files from the internet. All web browsers make use of HTTP to directly download files. Pausing or resuming failed downloads is not supported by HTTP.
• FTP - An internet standard and protocol that is used for the transmission of files from one computer to another, usually with username and password authentication. FTP clients are used for uploading and downloading files to a web server. FTP is one of the oldest protocols for downloading files.
• P2P - Files are downloaded through a desktop program rather than a website. It is possible for anyone with internet access and P2P applications to download files from a P2P network that does not have a central server.

Misconceptions

Copying files to the same computer is sometimes incorrectly referred to as a download. When a file is being copied from one drive or folder to another on the exact same computer, it is simply 'copying' and not downloading. Copying a file from one computer to a different one is a download.