Default LaTeX font for all commands and definitions

What is the font that LaTeX uses as default for: the notmal text, the `\bfseries`, the `\itshape` etc and all commands and definitions in the table 43 at page 131 of this guide?

I have found some fonts in this directory: `C:\texlive\2011\texmf-dist\fonts\opentype\public\lm`. I suppose that the default font for math is `lmmath-regular.otf`, right?

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Are you looking for `\normalfont`? Or are you looking for `Computer Modern`? –  Seamus Aug 4 '12 at 10:29
@Seamus what is the difference between those ? however, i would to know what .otf file latex use for every command/definition –  FormlessCloud Aug 4 '12 at 10:35
@FormlessCloud most TeX systems do not use OTF files by default. My answer gives the font names, but they are usually used in `.pk` (bitmap) or `.pfb` (type1) form –  David Carlisle Aug 4 '12 at 10:47

So the 10pt roman font is `cmr10`, the italic `cmti10` bold (extended) `cmbx10` etc.
For mathematics the situation is more complicated as there is not a single font, different characters come from different fonts. The main math italic is `cmmi10` The main math symbol font is `cmsy10` with big brackets etc coming from `cmex10`.