can you tell me when to use the phrase "next weekend" or "this weekend" ? are they the same thing ? If today is Tuesday when is "this" weekend ? and when is "next" weekend.
"Next weekend" will always be the next following weekend.
As for "this" weekend it depends on context. For example, "What did you do this weekend?" refers to the weekend that has passed. The key word is "did" - as this is past tense "this weekend" can be inferred to be the weekend that has just gone. Similarly, "What will you be doing this weekend?" refers to the next following weekend.
It used to common for people to say "This coming weekend I will be..." or "This weekend just gone I was..." as this makes it clear what you are referring to.