**The seminar audience** consists mostly of staff and graduate students of the laboratory of mathematical logic at PDMI. The main topics of the laboratory are computability, mathematical logic, computational complexity, graph theory, algorithms, and theoretical computer science. Undergraduate students also attend the seminar. Announcements of the seminar are distributed via email lists and are posted on the website. The exact audience can not be predicted since everybody decides whether to come to or not on the basis of the seminar announcement.

**The duration of the talk** varies depending on a type of the presentation. The duration of a blackboard talk is 1.5 hours: two 45 minutes parts with a 5 minutes break. The duration of a beamer talk is 60 minutes.

**Our expectations.** We like understandable talks. In any case we prefer to hear and understand a small amount of information than to hear a large number of incomprehensible information. We feel good about the fact that we are reminded of all the definitions. We do not treat the talk as a formality.

We prefer to learn about proofs. It is much more important for us to understand the ideas of the proof than to understand the technical details.

We do not like very fast presentations. It is important that the audience would have the opportunity to ask questions before the topic changes cardinally.

Start your presentation with a plan of your talk. But be ready that the audience will not allow you to carry out the whole plan.

Tell about the motivation. It is important to explain why the problem you consider is interesting. Include the overview of the other studies of the subject.

Always make sure that the audience understands what is happening at the moment. Make pauses for questions. If some participants have stopped following the technical details, be sure that they can continue following the talk after you finish explanation of this details. Usually it is easy to understand whether the audience is following you or not. If it is not clear, stop and ask whether the participants missed something. It makes no sense to continue the talk if no one is following you.

It is better to use a blackboard during the presentation. Slides should be used only for demonstration of illustrations that are difficult to reproduce on your own. The advantage of a blackboard is that the information on it does not disappear as fast as it disappears on slides.

If you decided to use a beamer, please, think in advance how the information on your slides will be perceived. Usually it is recommended to show each slide for at least two minutes, so the number of slides should not be more than 30. Avoid switching slides backwards. Do not put a lot of text on the slides — participants should not be engaged in reading the slides. It is better if the information on a slide appears gradually, so it is easier to perceive it.