6. The computer-implemented method of claim 4 , further comprising: at a first time, providing first code to a client computing device, wherein the first code, when executed by the client computing device, is configured to provide the client computing device with access to the first sub-document; and at a second time, subsequent to the first time and in response to receiving the request to access the second sub-document, providing second code to the client computing device, wherein the second code, when executed by the client computing device, is configured to provide the client computing device with access to the second sub-document.
6. The computer-implemented method of claim 4 , further comprising: at a first time, providing first code to a client computing device, wherein the first code, when executed by the client computing device, is configured to provide the client computing device with access to the first sub-document; and at a second time, subsequent to the first time and in response to receiving the request to access the second sub-document, providing second code to the client computing device, wherein the second code, when executed by the client computing device, is configured to provide the client computing device with access to the second sub-document. 8. The computer-implemented method of claim 6 , further comprising: in response to receiving the request to access the document collection, providing document collection code to the client computing device, wherein the document collection code, when executed by the client computing device, integrates access to the first sub-document and the second sub-document into the document collection.