If you're converting from a LAMP to a MEAN stack, then you will have to either rewrite your existing code into JavaScript or integrate it in an invisible way. Keep in mind that there is no one size fits all solution for Web site development, and the right size for a project's needs depends on the users, browsers, devices, infrastructure in play, and the skills and knowledge of the development team. ">
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MEAN STACK TRAINING

There are some great reasons why many view the MEAN Stack as having the upper hand over the LAMP Stack:
Node.js lets you to write server side applications by using Javascript thereby releasing Javascript from the shackles of the web browser. Node.js is also faster and more scalable than other server side technologies including LAMP because of its non-blocking architecture.

AngularJS is an open source client-side Javascript framework that is developed and maintained by a few smart people at Google. Angular JS has been creeping into many projects for a bit while now and a few of the projects have front end parts powered by Angular JS. It has solved many development issues when making reusable, maintainable or testable client-side applications powered by Javascript. One of the great things about this framework is its powerful directives that evolve into domain-specific language, and keeping things highly testable and reusable.

MongoDB is a document-oriented database that allows you to store documents in JSON format, JSON stands for JavaScript Object Notation. MongoDB is therefore a format that JavaScript natively understands. If your server-side code is written in Javascript and your client-side applications are also in Javascript, then it makes sense to use a database with a JavaScript flavour. Given how MongoDB naturally responds in a format that's understood by the Javascript-driven Node.js, the code it takes to serialize and deserialize data is dramatically reduced. The most vital thing to note is while you may be using Mongo for some of your projects, you don't have to make a big blanket commitment to displace your old databases.
Relational databases like MySQL have been around for three decades and they surely have their place. It is just a matter of the application's objectives. MongoDB may be better in some cases and MySQL others. But fortunately this doesn't affect the MEAN acronym. The "M" in "MEAN" can stand for Mongo or MySQL. Critics of the MEAN stack sometimes point out that MongoDB may work well for small to mid-sized applications, but less so for large-scale applications that must service hundreds of millions of users.
If you're converting from a LAMP to a MEAN stack, then you will have to either rewrite your existing code into JavaScript or integrate it in an invisible way. Keep in mind that there is no one size fits all solution for Web site development, and the right size for a project's needs depends on the users, browsers, devices, infrastructure in play, and the skills and knowledge of the development team.