# How to use packages from TeX Live?

I downloaded the MacTeX and I am now using Texmaker to finish my algorithm homework.

When I try to add this line \usepackage{algorithms} in texmaker, it always keeps telling me that algorithms.sty is not found.

However TeX Live Utility shows that this package has been installed. How could I solve this?

• Welcome! There is no algorithms.sty in TeX Live. Please do not post screen shots of code. Instead, post a Minimum Working Example, if possible, or a Minimum Non-Working Example, if not. Not every package corresponds to a .sty file by the same name. You need to look at the documentation or package contents to figure out what it provides.
– cfr
Aug 28 '15 at 1:57

Not every TeX Live package, package, includes a .sty file by the same name, package.sty. Sometimes it does. Sometimes it doesn't. To figure out what a package provides, read its documentation or look inside its directories. Alternatively, in some cases, you can simply ask TeX Live Manager. For example,

tlmgr info algorithms

returns this:

package:     algorithms
category:    Package
shortdesc:   A suite of tools for typesetting algorithms in pseudo-code
longdesc:    Consists of two environments: algorithm and algorithmic. The algorithm package defines a floating algorithm environment designed to work with the algorithmic style. Within an algorithmic environment a number of commands for typesetting popular algorithmic constructs are available.
installed:   Yes
revision:    38085
sizes:       src: 53k, doc: 365k, run: 17k
relocatable: No
cat-version: 0.1
cat-date:    2015-08-03 05:43:12 +0200
cat-topics:  pseudocode
cat-related: alg
collection:  collection-science

So the package probably provides algorithm.sty, at least.

And, indeed,

ls \$(kpsewhich -var TEXMFMAIN)/tex/latex/algorithms/

confirms this:

algorithm.sty  algorithmic.sty

In addition to the general answer provided using shell commands, Mac users such as the OP can get this info by double-clicking the "algorithms" row in TeX Live Utility, which shows the documentation and all files associated with a given package.