Python is a general-purpose, high-level programming language whose design philosophy emphasizes code readability. Python claims to combine "remarkable power with very clear syntax", and its standard library is large and comprehensive. wikipedia.org

Structured Query Language (SQL) is a programming language designed for managing data in relational database management systems (RDBMS). wikipedia.org

Scrapy is a web crawling framework, which was designed for web scraping. It is open-source and written in Python. It is controlled using command line tools, that can be used to trigger the scrapers written in Python. wikipedia.org

Selenium is a portable software testing framework for web applications. Selenium provides a record/playback tool for authoring tests without learning a test scripting language (Selenium IDE). wikipedia.org

Beautiful Soup is a Python package for parsing HTML and XML documents (including having malformed markup, i.e. non-closed tags, so named after tag soup). It creates a parse tree for parsed pages that can be used to extract data from HTML, which is useful for web scraping wikipedia.org

Redis is an open-source, networked, in-memory, key-value data store with optional durability. It is written in ANSI C. The development of Redis is sponsored by VMware.