In this talk, I will summarize a basic theory and some previous studies
on modular forms and automorphic forms.
In particular, I will focus on those of one variable and those of half-integral weight.
They are the most basic and unusual, respectively.
If time permits, I will overview my study or future work.

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In Student Colloquium, we do not fix the end time. Though a nominal time is shown above, we mean neither that it will be so, nor that it was so.