  Multimodality Representation Learning, as a technique of learning to embed
information from different modalities and their correlations, has achieved
remarkable success on a variety of applications, such as Visual Question
Answering (VQA), Natural Language for Visual Reasoning (NLVR), and Vision
Language Retrieval (VLR). Among these applications, cross-modal interaction and
complementary information from different modalities are crucial for advanced
models to perform any multimodal task, e.g., understand, recognize, retrieve,
or generate optimally. Researchers have proposed diverse methods to address
these tasks. The different variants of transformer-based architectures
performed extraordinarily on multiple modalities. This survey presents the
comprehensive literature on the evolution and enhancement of deep learning
multimodal architectures to deal with textual, visual and audio features for
diverse cross-modal and modern multimodal tasks. This study summarizes the (i)
recent task-specific deep learning methodologies, (ii) the pretraining types
and multimodal pretraining objectives, (iii) from state-of-the-art pretrained
multimodal approaches to unifying architectures, and (iv) multimodal task
categories and possible future improvements that can be devised for better
multimodal learning. Moreover, we prepare a dataset section for new researchers
that covers most of the benchmarks for pretraining and finetuning. Finally,
major challenges, gaps, and potential research topics are explored. A
constantly-updated paperlist related to our survey is maintained at
https://github.com/marslanm/multimodality-representation-learning.
