The bookmarks in Firefox are stored in a file inside the [[profiles|profile folder]]. You have a few choices. For just the bookmarks you can use the old computer to create a backup file, and then restore the backup file into the new computer. Fore details see [[Backing up and restoring bookmarks]]. You can copy more than just the bookmarks, for example you can also copy passwords, cookies, browsing history and settings. For details see [http://kb.mozillazine.org/Profile_backup Profile backup - MozillaZine Knowledge Base] or [[Backing up your information]]. There are some add-ons and utilities that can make this process easier. The first one is the [https://addons.mozilla.org/en-US/firefox/addon/2109/ FEBE] add-on which can be used to copy a profile. Another option is the free [http://mozbackup.jasnapaka.com/ MozBackup] utility.