OpenComputers

OpenComputers is a mod that adds programmable, modular computers. It was added in 1.2 for the modpack.

Computers
A computer, officially an OpenComputer (note the singular), is a small network of different components, typically confined within and connected to a case. All cases have two slots for RAM, a CPU socket, and depending on the tier, hard drive bays and expansion card slots. Typically, a case is accompanied by a monitor and a keyboard.

Components
A component is a modular part of a computer. Different components unlock different capabilities, and higher tiers typically offer more functions that their lower-tiered counterparts.

Internal components
Internal components are components that are inserted inside cases.

CPU
While it does not provide any callbacks or storage, the CPU is needed by a computer. In real life, a CPU provides all the maths required by the system, however, in OpenComputers, it enables the computer to access more components. If the number of components exceeds what is allowed by the CPU, the computer will not boot. A tier 1 CPU can support 8 components, a tier 2 CPU can support 12, and a tier 3 CPU can support 16.

HDD
A hard disk drive, or HDD, is a component that is inserted into a hard drive bay (the top right and middle right slots in a case). It provides persistent long-term storage for a computer, and is typically where files are written. A computer can technically boot without one, but it will only be able to read and perform I/O on either a Floppy Disk or EEPROM. A tier 1 HDD has a capacity of 1 MB, a tier 2 HDD has a capacity of 2 MB, and a tier 3 HDD has a capacity of 4 MB. A Floppy Disk is a removable HDD with a capacity of 384 KB.

RAM
Random access memory, or RAM, is how computers store information temporarily. It stores the data required to be loaded quickly. It is like a really fast HDD. However, unlike a HDD, RAM is volatile and thus will be wiped when the computer is powered down. RAM comes in 6 tiers, with tier 1.0 being the lowest at 256 KB, and tier 3.5 being the highest at 1024 KB (or a megabyte).