Most of the developers will do the same kind of mistake. The first syntax has "/" in the href and it'll always point to http://localhost:8080/
which is the root for the tomcat. In the second syntax the "../" will consider the current directory and take one level up which is MyProject and tries to resolve the other part of the path.
General approach is to have the <base> tag which will point to the base directory of your application and all the other links in the jsp will use relative paths which will be resolved from the base directory given in the <base> tag. :-)