Abenteuer Informatik: summary and exam topics for the Vienna entrance test
The subject-knowledge part of the Informatics entrance test (about 35% of the score) rests on a single book: "Abenteuer Informatik: IT zum Anfassen für alle von 9 bis 99" by Jens Gallenbacher, currently the 4th edition. That is good news, because the material is clearly bounded and fully understandable without any programming.
One thing to know: the questions are often application-based. Memorising definitions is not enough. You should be able to work through the book's worked examples yourself, because many exam tasks are derived directly from them. This page summarises the exam-relevant topics for free, but it does not replace the book.
Practise subject-knowledge questions freeWhich topics are exam-relevant?
For the entrance test, seven topic areas from the book matter most. They cover the classic core of computer science: how you order data, shrink it, transmit it reliably and protect it, and where the limits of what is computable lie. If you master these seven topics and can rework the related examples, you have the subject-knowledge part well covered.
- Sorting: algorithms to put a list in order
- Compression: storing data with less space
- Networks: how data finds its way through the net
- Hashing: fast lookup via a checksum
- Cryptography: encrypting messages (e.g. Caesar)
- Error correction: detecting and fixing transmission errors (parity)
- Computability: what a computer can solve in principle
The seven topics in short
Sorting: a sorting algorithm turns an unordered list into a sequence, for example from small to large. The book shows intuitive methods such as repeatedly swapping neighbouring elements. What matters is not only the result but the cost: how many comparisons and swaps a method needs, and why some are faster than others.
Compression: the goal is to represent the same information using less storage. Frequent symbols get short codes and rare ones get long codes, so the whole message gets shorter with no loss of information. Typical tasks ask you to encode a text or estimate the bits saved.
Networks: data travels in packets through a net of many nodes. The topic explains how a packet is guided to its destination via intermediate stations (routing) and how to find a short or cheap path. Tasks often ask you to determine the best path in a small network.
Hashing: a hash function computes a number (the hash) from a data value, so you can find that value again quickly without searching everything. The book shows how a table is filled via hashes and what happens when two values land on the same slot (a collision).
Cryptography: encryption makes a message unreadable to outsiders. The classic entry example is the Caesar shift, where each letter is moved a fixed number of places in the alphabet. Tasks let you encrypt, decrypt, or crack a shift.
Error correction: bits can flip during any transmission. Extra check bits, such as a parity bit, let you detect an error and, depending on the method, even locate and fix it. Typical tasks: compute parity or find a flipped bit.
Computability: not every problem can be solved by a computer, no matter how fast it is. This topic outlines where the fundamental limits lie, for example that some questions are simply not decidable by any algorithm. Here understanding the idea counts more than a calculation.
Which chapters and which edition?
The test refers to the 4th edition of "Abenteuer Informatik". When buying or borrowing it, make sure it is the current edition, since chapter numbers can shift between editions.
To be honest: the exact exam-relevant chapter numbers are stated differently across sources. Some lists name chapters 2, 3, 9, 11, 12, 14 and 15; others add chapters 1 and 8 on top. So we deliberately give you no fixed list of numbers, but the topic areas above, which are reliably tested.
For the binding chapter list, always rely on the current-year official Infoblatt from TU Wien or Uni Wien. Only that tells you what actually applies to your test date. If you master the seven topics, you are safe regardless of whether a source names one chapter more or less.
How to study the book efficiently
Read chapter by chapter and rework every worked example yourself. Because the questions are application-based, reading alone does little: the material only sticks once you have decrypted a Caesar shift yourself or computed a parity by hand. Note one memory sentence and your own mini-example per topic.
Plan realistically. Subject knowledge is about 35%, while the cognitive part is half the score and is pure practice. If your time is tight, first secure the seven topics enough to solve the standard tasks, then put the rest into the cognitive part. Finally, test yourself with mixed questions under time pressure.
Frequently asked questions
Which Abenteuer Informatik chapters appear in the entrance test?
Sources give different numbers (often 2, 3, 9, 11, 12, 14, 15, some add 1 and 8). What is reliably tested are the topics sorting, compression, networks, hashing, cryptography, error correction and computability. The binding chapter list is in the official Infoblatt for your test year.
Which edition of Abenteuer Informatik do I need?
The 4th edition by Jens Gallenbacher. When buying or borrowing, check for the current edition, since chapter numbers can shift between editions.
Where can I buy or read Abenteuer Informatik?
The book is available in regular bookshops and online (Springer). You can often find it in university and city libraries in Vienna, so you can look at it before buying. This page summarises the exam-relevant topics but does not replace the book.
Is reading a summary enough, or must I work through the book?
For a few questions a summary may be enough, for most it is not. The questions are application-based and often come from the worked examples. Rework the examples yourself instead of only reading definitions.