What are “rc” files
config files
rc –> run commands
First Contentful Paint (FCP)
Time until the user sees an indication that the page is loading
Largest Contentful Paint (LCP)
- how quickly the main content of a web page is loaded
- the time from when the user initiates loading the page until the largest image or text block is rendered within the viewport
Cumulative Layout Shift (CLS)
Movement distance and impact of page elements during the entire lifetime of the document the user sees
First Input Delay (FID)
The browser time delay between the user’s first click and execution of application code
Example:
User clicks a button but eventhandler does not fire right away b/c page JS hasn’t finished loading
4 Web Vitals & tips for success
First Contentful Paint (FCP) - Respond quick
Largest Contentful Paint (LCP) - Get to the point
Cumulative Layout Shift (CLS) - Don’t move stuff
First Input Delay (FID) - Don’t load too much
What is the internet?
The internet is composed of many computers connected to each other and exchanging information.
These connections establish what’s known as a “network.”
When you connect to the internet, you’re connecting to a huge network consisting of many computers.
How computers talk to each other
- Computers and other devices have addresses.
- Computers send and receive information to and from each other with these addresses.
- When shared between computers, the information is turned into chunks of data the internet knows how to handle.
- Some computers, called servers, can send out information to other computers upon request.
Key components to Internet
- IP addresses
- Nodes and hosts
- Protocols
- Data packets
- Networking infrastructure
- Internet infrastructure
- Internet routing
- Domain names
IP Address
Computers use Internet protocol (IP) addresses to connect with one another through the internet
(similar to addresses we use to send postal mail)
Nodes and Hosts
Nodes - computers and devices connected to a network
Hosts - nodes that run applications that send and accept information from other nodes
Protocols
Protocol - a way of transmitting data between computers and other devices.
Most common protocols:
* Simple Mail Transfer Protocol (SMTP). This is used for email.
* Hypertext Transfer Protocol (HTTP). HTTP is used to connect to web pages on the World Wide Web (WWW).
* Transmission Control Protocol (TCP) - a standard that defines how to establish and maintain a network conversation by which applications can exchange data. TCP works with the Internet Protocol (IP), which defines how computers send packets of data to each other.
Data packets
- how bytes of data are packaged before traveling through the internet
- similar to normal packages that contain the parts of something that must be put together
Networking infrastructure
the physical devices that networks use to transmit data
Internet infrastructure
The infrastructure of the internet is built and supported by network service providers (NSPs).
By “infrastructure,” we mean the physical components that carry data through the internet. For example, these would include core routers, which take data and send it someplace else, and fiber optic cables, which carry data.
Internet routing
- In order for data to be sent to the right place over the internet, each data packet has routing information that tells it where to go. In this way, data on the internet is similar to mail you send through the post office. Each packet of data has information that tells it where it needs to be sent.
- Then a router, which sends data along the right route, takes the data, reads the information that says where it’s supposed to go, and sends it there.
- Each time the data goes from one router to another, it’s called a “hop.” Eventually, the data hops to your computer or another device.
Domain names
- A domain name is what you type into your browser, such as “Google.com,” “Yahoo.com,” or “Codecademy.com.” Domain names generally consist of two parts: Top-level domains (TLDs) and second-level domains (2LDs)
- TLDs are what follow the period in a domain name, like “.com” or other common TLDs like “.gov” or “.edu.”
- 2LDs precede the period in a domain name. For “Codecademy.com,” “Codecademy” is the 2LD. Generally, a 2LD can be whatever you want it to be — as long as it’s not already in use.
CPU
Central Processing Unit
aka processor or microprocessor
CPU Core
Essentially, a core is a CPU itself, a separate device inside the main CPU chip. This means that it has the ability to do just one thing at a time.
However, modern computers have the ability to support more than one core inside the main chip.
What is usually meant by the term “elastic”?
- Ability to scale
- Elastic cloud computing is the ability to quickly expand or decrease computer processing, memory, and storage resources to meet changing demands.
VPS
Virtual Private Server
* a slice of a server
* a virtual machine that provides virtualized server resources on a physical server that is shared with other users. With VPS hosting, you get dedicated server space with a reserved amount of resources, offering greater control and customization than shared hosting.
VPC
Virtual Private Cloud
a secure, isolated private cloud hosted within a public cloud.
Types of DNS Records
A Record
Maps name to IP Address
i.e. drinkvsdrink.com → 23.23.185.61
CNAME
Maps name to name
i.e. blog.drinkvsdrink.com → drinkvsdrink.com
Proxy Server (Forward Proxy)
allows multiple clients to route traffic to an external network.
e.g. a business may have a proxy that routes and filters employee traffic to the public Internet. A reverse proxy, on the other hand, routes traffic on behalf of multiple servers.
