Collection of web pages. By theme. Old Fund

The collection of web pages is the main way to carry out the legal deposit of online publications. It is carried out with crawling robots that go through the previously selected URLs and save everything they have linked to the frequency, depth and size that is determined. The result of these web collections are web files.

These are selective collections, they are made to complete mass collections, since they collect with greater depth and frequency a smaller sample of websites selected for their relevance to history, society and culture.
They are held several times a year in collaboration with the conservation centres of the autonomous communities and other specialised institutions.

The thematic ones, each Department of the National Library and each autonomous community maintains their thematic collections with the online resources they deem necessary to keep as part of the legal deposit.

网页采集是开展在线出版物法定缴送的主要途径。该工作通过网络爬虫（crawling robot）完成：爬虫将遍历预先选定的统一资源定位符（Uniform Resource Locator，URL），并按照预设的采集频次、爬取深度与规模限制，抓取并保存其关联的全部内容，最终生成网页文件集合。

此类采集属于选择性采集项目，旨在填补批量采集的覆盖缺口：相较于批量采集，选择性采集会针对因历史、社会与文化价值而入选的少量网站样本，以更高的爬取频次与更深的采集深度开展工作。该项目每年会同各自治区的馆藏保护中心及其他专业机构联合开展数次。

主题采集项目方面，国家图书馆各部门与各自治区可自行维护各自的主题资源采集馆藏，收录其认定需作为法定缴送馆藏予以留存的在线资源。