answers.
HTTP Request Headers ANS --contain meta information about the request being made
How do people access the web? ANS -1. Web Browsers (Chrome, Safari, etc.)
2. Mobile Devices
-varying screen sizes
-different interaction behavior
3. Screen Readers
-used by those with visual impairments
-read out contents of a computer screen to the user
-Americans with Disabilities Act (ADA): provides guidelines for destining websites that are accessible to
screen readers
What kind of model does the internet/web servers work on? ANS --client-server model
What are clients? ANS --the browsers that are accessing a resource over the internet (front-end)
What are servers? ANS --the computers that host the resource, such as a web page
-typically purpose built computers for hosting and can handle many requests at one time (back-end)
What is installed on web servers to "serve" the web pages? ANS -Special Software
-I.e. Apache, Nginx
-can use any operating system - Windows, Mac, Linux
,What is the most popular operating system and why? ANS --Linux because it has low cost and easy
remote management
How do web hosting companies handle lots of traffic? ANS --they run large specialized computers that
act as web servers for many websites
For a website to be publicly accessible, it needs to be posted on _______________ ANS --a publicly
accessible web server, typically provided by a large web hosting company
How is web hosting economy of scale? ANS --large data centers can house thousands of servers
efficiently by centralizing cooling, maintenance, and physical security
What does virtualization do? ANS --allows powerful servers to run many virtual machines which each
have access to a portion of the host machine's resources. Most web hosting companies operate thix
way.
-introduces some security risk
VPS ANS --Virtual private server
Hypervisor ANS --software that manage virtual machines on a server (VMware, Xen, etc.)
Cloud Web Hosting ANS --allows you to create virtual servers with a nearly unlimited pool of resources
to draw from
-cloud providers usually provide scaling, useful management tools, and other servers like DNS< network
configuration, databases, etc.
-I.e. Amazon Web Services, Google Cloud, Digital Ocean, Microsoft Azure
Pros and Cons of Cloud Web Hosting ANS -Pros
-cheaper (pay per usage)
-easier
-usually automatically managed
, Cons
-some security risk
-less control (controlled by people who work with cloud)
-vendor lock-in
How are websites accessed? ANS --by a URL
What does URL stand for? ANS -Uniform Resource Locator
What are the parts of a URL? ANS -1. Protocol or Scheme: "http://" for unsecure or "https://" for secure
connections
2. Domain: the main address of the website, "google.com"
-may include a subdomain like "www.google.com" or "docs.google.com"
-the .com part is called the TLD (Top Level Domain) and can be many options
3. Path and/or filename: "/folder/index.html"
-does not always include a file extension, html is default
-domain with no path is called the "root" of the domain
HTTP ANS --Hypertext Transfer Protocol
HTTPS ANS --Hypertext Transfer Protocol Secure
-all data is encrypted between your browser and the web server
-should almost always be used
TLD ANS --Top Level Domain
-I.e. ".com"