The Informationsverbund Berlin-Bonn (IVBB), the secure network of the german government , was breached by an unknown hacker group. Okay, a secure government network might be a worthy target for an attack, but your network not, right? Do you use the same password for multiple accounts? There were multiple massive data breaches in the past. Have you ever checked if your data were also compromised? I can recommend haveibeenpwned.com. If you want to have some fun, scan GitHub for -----BEGIN RSA PRIVATE KEY-----. Do you use a full disk encryption on your laptop or PC? Do you sign and/ or encrypt emails using S/MIME or PGP? Do you use different passwords for different services? Do you use 2FA/ MFA to secury importan services? Do you never work with admin privileges when doing normal office tasks? No? Why? Because it’s uncomfortable to do it right, isn’t it?
Complexity, in general usage, tends to be used to characterize something with many parts in intricate arrangement.
Following this disambiguation, and assuming that “many” means N > 2, all systems with at least two or more components are complex. But that would be an exaggeration, right?
Why is information technology complex?
Most systems in information technology (IT) are complex. Almost everything we are working with, consists of two or more components, regardless if it is hardware or software. But it’s a question of the perspective. If you look at a system from a higher level, you will only be able to identify some of the greater components. If you look closer at it, you will be able to identify more, smaller components. Every system consists of hardware and software. Hardware is nothing without software. Think of a storage system, with all those disks, controllers, disk enclosures, firmware etc. Or think bigger: A complete infrastructure based on a VMware vSphere cluster with multiple servers, network switches, SAN switches, storage systems, synchronous mirroring between data centers etc. The system can be split into its components and sub-components. And each component and sub-component is more or less important of the operational function of the whole system. Adding more features makes a system even more complex. With each added feature or modified feature, the probability rises, that something breaks or doesn’t work as expected.