1. A transaction processing system comprising: a client; a server; and at least one connector therebetween, wherein the client is operable to: a) initiate an application request on the end user application in a first language with a first application program, wherein the end user application is a web browser; b) transmit the application request to the server and converting the application request from the first language of the first end user application to a form for the mapping support language running on an application server, wherein the end user application is connected to the application server through a web server, and the web server comprises a connector; c) process said application request on the application server; and d) transmit a response to the application request from the application server to the end user application, and converting the response to the application request from the mapping support language running on the application server to the first language of the first end user application, wherein the connector comprises invocation and transformation capabilities, wherein the connector comprises a language metamodel to define data structures that represent connector interfaces, wherein the language metamodel indicates a source language, a target language, and a mapping between the source language and the target language, wherein the language metamodel comprises declaration text that is not editable, wherein the connector comprises a type descriptor metamodel that is language neutral and that defines a physical realization, a storage mapping, and a plurality of constraints, wherein the type descriptor metamodel provides a physical representation of individual fields of a given data structure, wherein the type descriptor metamodel provides data types mapping between languages, wherein the connector comprises invocation metamodel data, application domain interface metamodel data, transaction message metamodel data, and type descriptor metamodel data, wherein the connector is configured to (i) convert the application request from the first language of the first end user application as a source language to the language running on the application server as a target language, and (ii) convert a response to the application request from the language running on the application server as a source language to the first language of the first end user application as a target language, each comprise: a) invoking connector metamodels of respective source language and target mapping support language; b) populating the connector metamodels with metamodel data of each of the respective source language and target mapping support language, the metamodel data capturing with 3270 screen formatting for 3270-based applications, the metamodel data including a map, a mapset, and a mapfield, wherein the mapset comprises a plurality of programming attributes, wherein the programming attributes comprise a storage operand that varies based on a language of an application program; and c) converting the source language to the mapping support language.