Blob：
the blob is the standard array and unified memory interface for the framework. The details of blob describe how information is stored and communicated in and across layers and nets. A Blob is a
wrapper over the actual data being processed and passed along by Caffe, and also under the hood provides synchronization capability between the CPU and the GPU. Mathematically, a blob is an N-dimensional array stored in a C-contiguous fashion.
所以說，Blob是一個標準的數組，爲訓練網絡提供了一個存儲的接口。Blob詳細的描述了信息在層與層、網絡與網絡中是怎麼傳遞交互的。
直白一點的說：Blob就是一個數組。