What is Agile
If we go by dictionary definition.. This is an adjective which means "able to move quickly and easily".
Also relating to or denoting a method of project management, used especially for software development, that is characterized by the division of tasks into short phases of work and frequent reassessment and adaptation of plans.
"agile methods replace high-level design with frequent redesign"
Origin of this word is late Middle English: via French from Latin agilis, from agere ‘do’.
Let's keep it simple in terms of software development it is nothing but uncovering better ways of developing
software by doing it and helping others do it. It's all what Manifesto for Agile Software Development says
High performance teams consider additional values beyond what Agile defines.
An organization should define a culture that aligns with it’s values, so the organization understands behavioral expectations. Cultural norms are a set of rules.
A number of development methods (process, rules) are aligned with Agile values. Scrum is one of the great Agile aligned development method.
Kanban and XP are another good fit for purpose methods or rules.
On top of development methods (process, rules), organizations should look at awesome Agile aligned practices.