kate: 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/kate - from package: kdesdk

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

On Debian possible default full paths are:

/usr/bin/kate - from package: kate

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

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