JSP Servlet

jsp是后端技术，html5和js，css是前端技术，可比性不大，如果硬要对比的话，确实jsp在出现了诸多mvc框架后，jsp只作为v层的角色也逐渐被诸如freemarker，velocity等技术在运行效率，尤其和前端人员的可读性方面落入了下峰，jstl标签技术也只是弥补这方面的不足，但性能方面确实不敢恭维。

你要是选别的框架，可以不学JSP，至少要学Servlet，这是所有框架的基础。

JAVASCRIPT :

Javascript is a dynamic computer programming language. It is lightweight and most commonly used as a part of web pages, whose implementations allow client-side script to interact with the user and make dynamic pages. It is an interpreted programming language with object-oriented capabilities.

Main features:

• JavaScript is a lightweight, interpreted programming language.
• Designed for creating network-centric applications.
• Complementary to and integrated with Java.
• Complementary to and integrated with HTML.
• Open and cross-platform

SERVLETS :

Java Servlets are programs that run on a Web or Application server and act as a middle layer between a request coming from a Web browser or other HTTP client and databases or applications on the HTTP server. Using Servlets, you can collect input from users through web page forms, present records from a database or another source, and create web pages dynamically.

Main features:

• Servlets execute within the address space of a Web server. It is not necessary to create a separate process to handle each client request.
• Servlets are platform-independent because they are written in Java.
• Java security manager on the server enforces a set of restrictions to protect the resources on a server machine. So servlets are trusted.
• The full functionality of the Java class libraries is available to a servlet. It can communicate with applets, databases, or other software via the sockets and RMI mechanisms that you have seen already.

JSP :

JavaServer Pages (JSP) is a technology for developing web pages that support dynamic content which helps developers insert java code in HTML pages by making use of special JSP tags, most of which start with <% and end with %>. A JavaServer Pages component is a type of Java servlet that is designed to fulfill the role of a user interface for a Java web application. Web developers write JSPs as text files that combine HTML or XHTML code, XML elements, and embedded JSP actions and commands. Using JSP, you can collect input from users through web page forms, present records from a database or another source, and create web pages dynamically.

Main features:

• Performance is significantly better because JSP allows embedding Dynamic Elements in HTML Pages itself instead of having a separate CGI files.
• JSP are always compiled before it's processed by the server unlike CGI/Perl which requires the server to load an interpreter and the target script each time the page is requested.
• JavaServer Pages are built on top of the Java Servlets API, so like Servlets, JSP also has access to all the powerful Enterprise Java APIs, including JDBC, JNDI, EJB, JAXP etc.
• JSP pages can be used in combination with servlets that handle the business logic, the model supported by Java servlet template engines.