RedPower 2, the continuation of RedPower, is a mod originally focused on Redstone circuitry, which has however grown and also offers many other non-Redstone-related blocks, machines and items. Due to RedPower 2 not being updated past Minecraft version 1.4.7, there are several remakes and continuations of it, such as Project Red and Blue Power.
RedPower 2 consists of four modules: Core, Digital, Mechanical and Compat[ibility]. Core is the main part of the mod and has to be installed for any other modules to work, whereas the three others are independent and can be installed in any combination.
Core
RedPower Core provides basic functionality necessary for the other modules. This includes the Alloy Furnace, Handsaws and Microblocks.
Digital
RedPower Digital is the Redstone-focused part of the mod - it includes Red Alloy Wire, its insulated, bundled and jacketed versions, one-block Redstone logic circuits and lamps in many shapes and colors.
Mechanical
RedPower Mechanical includes various kinds of machines, ores, volcanoes, plants, the Blutricity power system, tubes to transport items and liquids, computers, and Support Frames.
Compat
RedPower Compat is a small module that allows interfacing with other mods. Currently it only includes the Blulectric Engine, an engine that produces MJ when supplied with Blutricity.
