# 2. Updating files with `convert-ly`

The LilyPond input syntax is routinely changed to simplify it or improve it in different ways. As a side effect of this, the LilyPond interpreter often is no longer compatible with older input files. To remedy this, the program `convert-ly` can be used for upgrading files to newer versions of LilyPond.

其他语言：deutsch, español, français, magyar, italiano, 日本語。
About automatic language selection.

#### LilyPond — Usage v2.18.2 (稳定分支).