One user have installation guide for Apache Solr but we do not have guide for Apache Lucene. It is kind of deliberate omission. There is an easy way to use Lucence on the command line. In most of the situations possibly you’ll use Apache Solr and when you’ll realize the need to utilize Apache Lucene, then you’ll not need our help on installation. Solr is based on a Java library which is known as Lucene. Apache Lucene is a search engine software library. Lucene has been ported to other programming languages including Perl, PHP, C#, C++, Python, Ruby.
The closest comparison of Lucene can be with Linux kernel. While Solr is like any GNU/Linux distribution such as CentOS or Ubuntu. It is possible to create custom software using Lucene. Apache Solr is one of the well known open-source software which uses Lucene. The world of Lucene is larger.
Lucene is a Java library which provides full-text search features. But to use Lucene, we need to write some code top of it use those features. Apache Solr is ready to use solution, which provides an extra set of features on top of Lucene. Thus, Solr supports several query parsers, transformers, caching and a full analysis pipeline without writing code, using some HTTP API. That is said. Solr is built around Lucene but it is not just an HTTP-wrapper around Lucene. Also, Lucene has horizontal scalability. You need to enter the Lucence world, in cases, for example, you need is to embed search functionality into a desktop application or mobile application.
Several projects use Lucence, including Apache Nutch, Apache Solr, Elasticsearch, Compass, CrateDB, DocFetcher, Swiftype to name a few. It is common to combine some of the software in a real-life use case.
Apache Lucence project itself has a dedicated webpage on Solr. You’ll choose Lucence directly when you are a programmer who wants full control over almost all the internals of Lucene.