# A mountain tour of kdb+ and the q programming language

## TL;DR

• Kdb+ is an in-memory, column-store database optimized for time series. It has a tiny footprint and is seriously quick.
• The q vector-programming language is built into kdb+. It supports SQL-style queries.
• Q expressions are interpreted in a REPL.
• Tables, dictionaries and functions are first-class objects..
• Kdb+ persists objects as files. A large table is stored as a directory of column files.
• Explicit loops are rare. Iteration over lists is implicit in most operators; otherwise mostly handled by special iteration operators.
• Parallelization is implicit: operators use multithreading where it helps.
• Interprocess communication is baked in and startlingly simple.