A method of providing information regarding a recommended content item to at least one device among a plurality of devices associated with a user account, by a server, the method comprising: storing content data corresponding to a plurality of content items in a content database, the content data comprising: content type information corresponding to the plurality of content items, title information corresponding to the plurality of content items, and genre information corresponding to the plurality of content items, receiving user history information corresponding to a plurality of previously-viewed content items among the plurality of content items from the plurality of devices associated with the user account (S340, S440, S540), the user history information comprising: viewing time information corresponding to the time at which the plurality of previously-viewed content items was viewed, viewing device information corresponding to the device upon which the plurality of previously-viewed content items was viewed, and reproduction duration information corresponding to the duration of the plurality of previously-viewed content items; analyzing the user history information by the server (S360, S460, S560); receiving a request from at least one device among the plurality of devices; selecting at least one content item which is expected to be of interest to a user among the plurality of content items, as the recommended content item, based on the analysed user history information and context information including a recommendation item request time and device information of the at least one device from which the request is received; and transmitting information regarding the recommended content item to the at least one device to display the information regarding the recommended content item on the at least one device, wherein the recommended content item comprises a video, and wherein the information regarding the recommended content item includes a thumbnail image representing the recommended content item, the thumbnail image being based on the user history information. storing content data corresponding to a plurality of content items in a content database, the content data comprising: content type information corresponding to the plurality of content items, title information corresponding to the plurality of content items, and genre information corresponding to the plurality of content items, content type information corresponding to the plurality of content items, title information corresponding to the plurality of content items, and genre information corresponding to the plurality of content items, receiving user history information corresponding to a plurality of previously-viewed content items among the plurality of content items from the plurality of devices associated with the user account (S340, S440, S540), the user history information comprising: viewing time information corresponding to the time at which the plurality of previously-viewed content items was viewed, viewing device information corresponding to the device upon which the plurality of previously-viewed content items was viewed, and reproduction duration information corresponding to the duration of the plurality of previously-viewed content items; viewing time information corresponding to the time at which the plurality of previously-viewed content items was viewed, viewing device information corresponding to the device upon which the plurality of previously-viewed content items was viewed, and reproduction duration information corresponding to the duration of the plurality of previously-viewed content items; analyzing the user history information by the server (S360, S460, S560); receiving a request from at least one device among the plurality of devices; selecting at least one content item which is expected to be of interest to a user among the plurality of content items, as the recommended content item, based on the analysed user history information and context information including a recommendation item request time and device information of the at least one device from which the request is received; and transmitting information regarding the recommended content item to the at least one device to display the information regarding the recommended content item on the at least one device, wherein the recommended content item comprises a video, and wherein the information regarding the recommended content item includes a thumbnail image representing the recommended content item, the thumbnail image being based on the user history information.