What are annotations and how do they actually work for frameworks like Spring?

Question

I am new to Spring and now a days I hear a lot about Spring Framework. I have two sets of very specific questions:

Set No. 1:

• What

Answer 1

What are annotations in general ?

Annotations are a convienient way of configuration, which could also be done using explicit configuration files, like deployment descriptors.

How does annotations works specifically with Spring framework ?

In spring they are used for dependency injection and many other purposes

Can annotations be used outside Spring Framework or are they Framework specific ?

Yes you can even write your own annotations. They have been introduced in java 1.5 for i.g. suppresing warnings.

What module of Spring Framework is widely used in Industry ?

The spring core module is used in all applications and therefore mostly used.

You should also browse the Documentation to get a first impression what the spring framework and its modules cover.