What is pipe in Angular?

 In Angular, a pipe is a feature that allows you to transform or format data before it is displayed in the template. Pipes are a form of pure functions that take an input value and return a transformed output value. You can use pipes to filter, sort, group, format, or otherwise manipulate data in various ways.

Pipes are defined in Angular using the @Pipe decorator, which takes a name parameter that specifies the name of the pipe. For example, the following code defines a custom pipe called "myPipe":

import { Pipe, PipeTransform } from '@angular/core';

@Pipe({
  name: 'myPipe'
})
export class MyPipe implements PipeTransform {
  transform(value: any, arg1: any, arg2: any): any {
    // Pipe logic goes here
  }
}

The transform method of the pipe takes an input value, as well as any additional arguments that you might want to pass in, and returns the transformed output value. You can then use the pipe in a template to transform data before it is displayed, like this:

<div>{{ myValue | myPipe: arg1: arg2 }}</div>

In this example, myValue is the input value that you want to transform, and arg1 and arg2 are any additional arguments that you want to pass to the pipe. The myPipe pipe then takes the input value and returns the transformed output value, which is displayed in the div element.

Angular comes with several built-in pipes, such as DatePipe, UpperCasePipe, LowerCasePipe, and JsonPipe, but you can also create your own custom pipes to suit your specific needs.