ECTS (European Credit Transfer System):
A bit of context: One of the (many) goals of European unification was the consistency and comparability of European academic degrees. To this end, a uniform way of judging the performance of students in academic programs is intended. It comprised (among others) rules regarding qualification goals, work load, and grading schemes.
In this context, the ECTS credit point was created as a unit of work load. ECTS measure that quantitative workload of a student. One ECTS point is equal 30 hours of actual work. Hence, if you take a, say, course of 4 ECTS, you should plan on spending 120 hours on it - we certainly expect you to do so!
Note that ECTS are NOT a measure of performance but only of quantity. ECTS are award in addition to, not instead of grades. Grades in this context are sometimes refered to as “ECTS grades”.
Sometimes, in particular in German texts, ECTS are also called “Leistungspunkte” (LP) - this is the same thing.
SWS is a abbreviation of Semesterwochenstunde – hours per week per semester. Hours here refers to “academic hours”, which only last 45 minutes. SWS indicates the duration of instruction in class. For example, a course designated as 2 SWS means that the class will take place during 2*45 minutes per week, for the duration of one semester (15 weeks). Unlike ECTS, however, SWS does NOT specify the total workload for a student; typically, SWS hours are accompanied by unspecified homework, independent study, etc. Hence, ECTS gives you an idea of total workload; SWS gives you and idea how much of that time should can expect to spend in class on campus.
LP is the abbrevivation for Leistunspunkt; it is the German equivalent to ECTS (see above).
LN is the abbreviation of Leistungsnachweis (proof of performance). In some study programs, these proofs are required and can take the form of homework assignments, independent studies, etc. In the computer science and computer engineering program, these proofs of performance are not typically used. If you see those in an announcement, you should talk to whoever offers that course.
TN is the abbreviation of Teilnahmenachweis (proof of attendance). In some study programs, these proofs are required. They are typically not used and extremely rare (but not forbidden either) in the computer science or computer engineering programs – we prefer you know something rather than you simply sat in a class. If you see those in an announcement, you should talk to whoever offers that course.
TS is the abbreviation of Teilnahmeschein (certificate of attendance). This is a synonym for Teilnahmenachweis / TN. See there.