annotate: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/annotate - from package: gd-progs

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/annotate - from package: libgd-tools

You may install the required package with command apt-get install {package}

Error in other languages:
annotate: bevel nie gevind nie
annotate: comandă negăsită
annotate: comando não encontrado
annotate: commande introuvable
annotate: command not found
annotate: käsku ei ole
annotate: không tìm thấy lệnh
annotate: komanda nerasta
annotate: Kommando nicht gefunden.
annotate: kommandot finns inte
annotate: komut yok
annotate: nie znaleziono polecenia
annotate: níor aimsíodh an t-ordú
annotate: no se encontró la orden
annotate: no s'ha trobat l'ordre
annotate: opdracht niet gevonden
annotate: parancs nem található
annotate: perintah tidak ditemukan
annotate: príkaz nenájdený
annotate: příkaz nenalezen
annotate: команда не найдена
annotate: командата не е открита
annotate: 命令找不到
annotate: コマンドが見つかりません