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Check out our glossary of common DevOps, monitoring and development terms and definitions.

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Cumulative Layout Shift (CLS)

Cumulative Layout Shift (CLS) is a core Web Vitals metric and it calculates the shifting of elements while the page is being downloaded and rendered.


In computer science, a cache is a storage location used to temporarily store data used by servers, apps, and browsers to speed load times.


DNS Lookup time

DNS stands for Domain Name System, a server or set of servers that store a record of domain names and their associated IP addresses.


First Input Delay (FID)

First Input Delay (FID) is the metric that calculates the time it takes for the browser to respond to the first client request. It’s measured in milliseconds.


HTTP Requests

An HTTP request is made from a client to a host located on the server in order to receive a resource needed to build the content.


JVM Threads

Learn what a thread is in Java. Discover the benefits of using JVM threads, how to work with and monitor them to ensure fast and efficient applications.


Largest Contentful Paint (LCP)

Largest Contentful Paint (LCP) is a Core Web Vitals metric that measures how long it takes a website to render the largest part of the content on the screen. In most cases, LCP refers to the content above the fold rather than the entire page.


Render time

Render time is the metric that refers to the time it takes for a website or web app to load enough that the user can actually interact with the page.

Response Time

Response time refers to the amount of time it takes for a server to respond to a client's request and is measured in milliseconds.


SSL Certificate

An SSL certificate is a digital certificate that provides authentication for a website is and is used to ensure internet security by preventing any third party with malicious intent from intercepting, reading, or modifying any information transmitted.

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