See also the List of all programs and the program category.
Page 31, Column 2, Paragraph(s) 4, Core Rule Book
Program: A Runner card type that is installed and grants him various abilities.

Programs are a type of card the Runner installs in his/her rig. They are often used in various ways during runs, but can have other utility as well. Unlike resources and hardware, the Runner can only have a certain number of programs installed at once. The Runner can never have programs with a combined memory cost greater than his/her total available memory units.

Page 11, Column 1, Paragraph(s) 1-4, Core Rule Book

Programs are the digital tools at the Runner's disposal, primarily as a means of intrusion.

The Runner installs programs in his rig by paying an install cost.

Programs are the only card type that have a memory cost. The memory cost of his installed programs can never exceed his current memory limit.

The Runner uses a program subtype called an icebreaker to break ice subroutines during runs. An icebreaker's strength must be equal to or greater than the ice it is interacting with.

Page 15, Column 1, Paragraph(s) 12, Core Rule Book
To install a program, the Runner pays the program's install cost and places it in his program row. Each program also has a memory cost. The Runner cannot have programs installed that have a combined memory cost greater than his available memory units (MU).
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