Internet is a network infrastructure that connects millions of computers and users worldwide. Increasing interest and access to the worldwide web have made the web as a potentially suitable medium for Computer Aided Learning (CAL). A web based presentation (courseware) is a collection of individual web pages having spatial and temporal objects in it. Spatial objects need to be organised in a two dimensional space, and temporal objects need to be sequenced. Our aim in this thesis is to provide an authoring toolkit which supports the author as much as possible to think in high-level domain oriented terms from which we generate a set of low-level spatial and temporal constraints automatically.  A syntax-directed translation and a grammar are used for this purpose. We have developed a grammar that is suitable for specifying the spatial and temporal constraints in a page. A Concept Graph Model, which is a directed acyclic graph is used to organise a web based presentation of the courseware. The authoring and presentation tool kits developed as part of this thesis work are evaluated by applying them to a real life problem. In this application, the author has developed a courseware on Assembly Language for a first year course in Computer Science. The input for the authoring too], in this case, were made available by the author as Microsoft Word document and as slides in Microsoft Power Point. The authored material is used by about twenty five students as a way of evaluation. The conclusions are, it is relatively easy to develop courseware using our authoring toolkit and incremental development of the courseware is simple . The authored courseware is found by students to be very useful in Computer Aided Learning