JNDI: Java Naming and Directory Interface is an API used to connect your Java applications remotely with EJB components, database drivers, directory services and naming services. Directory services include the Domain Naming Service (DNS). The APIs allow you to access LDAP servers and services running LDAP front ends including Novell Directory Services (NDS), Microsoft Active Directory (AD) and Network Information Services (NIS). Providers of naming and directory services implement JNDI SPI (service provider interface) to provide interfaces to access the services from Java programs.

JNI: Java Native Interface. As with other uses of the word “native” this is the low-level interface used in advanced development for accessing native libraries in non-Java applications. JNI is replacing NMI, native Method Interface.

JSP: Java Server Pages and text pages that contain both HTML and short pieces of Java code (called scriptlets) allowing for template driven dynamic web pages.

JTA: Java Transaction API. An API for implementing distributed, transaction based applications.

JVM: Java Virtual Machine. This is what must be installed on a system for it to run Java programs. It is installed with browsers, servers, operating systems and it understands the non-intuitive instructions that your Java compiler turned your Java files into. Having a standard virtual machine creates something of a standardized platform to develop for, a key component of Sun’s “write once- run anywhere vision.” Distributed computing in Java means that some components are interrelating with components running on JVMs on other systems.